/* * Copyright (c) 2003, 2007, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.util; import java.io.BufferedWriter; import java.io.Closeable; import java.io.IOException; import java.io.File; import java.io.FileOutputStream; import java.io.FileNotFoundException; import java.io.Flushable; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.io.PrintStream; import java.io.UnsupportedEncodingException; import java.math.BigDecimal; import java.math.BigInteger; import java.math.MathContext; import java.nio.charset.Charset; import java.text.DateFormatSymbols; import java.text.DecimalFormat; import java.text.DecimalFormatSymbols; import java.text.NumberFormat; import java.util.Calendar; import java.util.Date; import java.util.Locale; import java.util.regex.Matcher; import java.util.regex.Pattern; import sun.misc.FpUtils; import sun.misc.DoubleConsts; import sun.misc.FormattedFloatingDecimal; /** {@collect.stats} * {@description.open} * An interpreter for printf-style format strings. This class provides support * for layout justification and alignment, common formats for numeric, string, * and date/time data, and locale-specific output. Common Java types such as * <tt>byte</tt>, {@link java.math.BigDecimal BigDecimal}, and {@link Calendar} * are supported. Limited formatting customization for arbitrary user types is * provided through the {@link Formattable} interface. * * <p> Formatters are not necessarily safe for multithreaded access. Thread * safety is optional and is the responsibility of users of methods in this * class. * * <p> Formatted printing for the Java language is heavily inspired by C's * <tt>printf</tt>. Although the format strings are similar to C, some * customizations have been made to accommodate the Java language and exploit * some of its features. Also, Java formatting is more strict than C's; for * example, if a conversion is incompatible with a flag, an exception will be * thrown. In C inapplicable flags are silently ignored. The format strings * are thus intended to be recognizable to C programmers but not necessarily * completely compatible with those in C. * * <p> Examples of expected usage: * * <blockquote><pre> * StringBuilder sb = new StringBuilder(); * // Send all output to the Appendable object sb * Formatter formatter = new Formatter(sb, Locale.US); * * // Explicit argument indices may be used to re-order output. * formatter.format("%4$2s %3$2s %2$2s %1$2s", "a", "b", "c", "d") * // -> " d c b a" * * // Optional locale as the first argument can be used to get * // locale-specific formatting of numbers. The precision and width can be * // given to round and align the value. * formatter.format(Locale.FRANCE, "e = %+10.4f", Math.E); * // -> "e = +2,7183" * * // The '(' numeric flag may be used to format negative numbers with * // parentheses rather than a minus sign. Group separators are * // automatically inserted. * formatter.format("Amount gained or lost since last statement: $ %(,.2f", * balanceDelta); * // -> "Amount gained or lost since last statement: $ (6,217.58)" * </pre></blockquote> * * <p> Convenience methods for common formatting requests exist as illustrated * by the following invocations: * * <blockquote><pre> * // Writes a formatted string to System.out. * System.out.format("Local time: %tT", Calendar.getInstance()); * // -> "Local time: 13:34:18" * * // Writes formatted output to System.err. * System.err.printf("Unable to open file '%1$s': %2$s", * fileName, exception.getMessage()); * // -> "Unable to open file 'food': No such file or directory" * </pre></blockquote> * * <p> Like C's <tt>sprintf(3)</tt>, Strings may be formatted using the static * method {@link String#format(String,Object...) String.format}: * * <blockquote><pre> * // Format a string containing a date. * import java.util.Calendar; * import java.util.GregorianCalendar; * import static java.util.Calendar.*; * * Calendar c = new GregorianCalendar(1995, MAY, 23); * String s = String.format("Duke's Birthday: %1$tm %1$te,%1$tY", c); * // -> s == "Duke's Birthday: May 23, 1995" * </pre></blockquote> * * <h3><a name="org">Organization</a></h3> * * <p> This specification is divided into two sections. The first section, <a * href="#summary">Summary</a>, covers the basic formatting concepts. This * section is intended for users who want to get started quickly and are * familiar with formatted printing in other programming languages. The second * section, <a href="#detail">Details</a>, covers the specific implementation * details. It is intended for users who want more precise specification of * formatting behavior. * * <h3><a name="summary">Summary</a></h3> * * <p> This section is intended to provide a brief overview of formatting * concepts. For precise behavioral details, refer to the <a * href="#detail">Details</a> section. * * <h4><a name="syntax">Format String Syntax</a></h4> * * <p> Every method which produces formatted output requires a <i>format * string</i> and an <i>argument list</i>. The format string is a {@link * String} which may contain fixed text and one or more embedded <i>format * specifiers</i>. Consider the following example: * * <blockquote><pre> * Calendar c = ...; * String s = String.format("Duke's Birthday: %1$tm %1$te,%1$tY", c); * </pre></blockquote> * * This format string is the first argument to the <tt>format</tt> method. It * contains three format specifiers "<tt>%1$tm</tt>", "<tt>%1$te</tt>", and * "<tt>%1$tY</tt>" which indicate how the arguments should be processed and * where they should be inserted in the text. The remaining portions of the * format string are fixed text including <tt>"Dukes Birthday: "</tt> and any * other spaces or punctuation. * * The argument list consists of all arguments passed to the method after the * format string. In the above example, the argument list is of size one and * consists of the {@link java.util.Calendar Calendar} object <tt>c</tt>. * * <ul> * * <li> The format specifiers for general, character, and numeric types have * the following syntax: * * <blockquote><pre> * %[argument_index$][flags][width][.precision]conversion * </pre></blockquote> * * <p> The optional <i>argument_index</i> is a decimal integer indicating the * position of the argument in the argument list. The first argument is * referenced by "<tt>1$</tt>", the second by "<tt>2$</tt>", etc. * * <p> The optional <i>flags</i> is a set of characters that modify the output * format. The set of valid flags depends on the conversion. * * <p> The optional <i>width</i> is a non-negative decimal integer indicating * the minimum number of characters to be written to the output. * * <p> The optional <i>precision</i> is a non-negative decimal integer usually * used to restrict the number of characters. The specific behavior depends on * the conversion. * * <p> The required <i>conversion</i> is a character indicating how the * argument should be formatted. The set of valid conversions for a given * argument depends on the argument's data type. * * <li> The format specifiers for types which are used to represents dates and * times have the following syntax: * * <blockquote><pre> * %[argument_index$][flags][width]conversion * </pre></blockquote> * * <p> The optional <i>argument_index</i>, <i>flags</i> and <i>width</i> are * defined as above. * * <p> The required <i>conversion</i> is a two character sequence. The first * character is <tt>'t'</tt> or <tt>'T'</tt>. The second character indicates * the format to be used. These characters are similar to but not completely * identical to those defined by GNU <tt>date</tt> and POSIX * <tt>strftime(3c)</tt>. * * <li> The format specifiers which do not correspond to arguments have the * following syntax: * * <blockquote><pre> * %[flags][width]conversion * </pre></blockquote> * * <p> The optional <i>flags</i> and <i>width</i> is defined as above. * * <p> The required <i>conversion</i> is a character indicating content to be * inserted in the output. * * </ul> * * <h4> Conversions </h4> * * <p> Conversions are divided into the following categories: * * <ol> * * <li> <b>General</b> - may be applied to any argument * type * * <li> <b>Character</b> - may be applied to basic types which represent * Unicode characters: <tt>char</tt>, {@link Character}, <tt>byte</tt>, {@link * Byte}, <tt>short</tt>, and {@link Short}. This conversion may also be * applied to the types <tt>int</tt> and {@link Integer} when {@link * Character#isValidCodePoint} returns <tt>true</tt> * * <li> <b>Numeric</b> * * <ol> * * <li> <b>Integral</b> - may be applied to Java integral types: <tt>byte</tt>, * {@link Byte}, <tt>short</tt>, {@link Short}, <tt>int</tt> and {@link * Integer}, <tt>long</tt>, {@link Long}, and {@link java.math.BigInteger * BigInteger} * * <li><b>Floating Point</b> - may be applied to Java floating-point types: * <tt>float</tt>, {@link Float}, <tt>double</tt>, {@link Double}, and {@link * java.math.BigDecimal BigDecimal} * * </ol> * * <li> <b>Date/Time</b> - may be applied to Java types which are capable of * encoding a date or time: <tt>long</tt>, {@link Long}, {@link Calendar}, and * {@link Date}. * * <li> <b>Percent</b> - produces a literal <tt>'%'</tt> * (<tt>'\u0025'</tt>) * * <li> <b>Line Separator</b> - produces the platform-specific line separator * * </ol> * * <p> The following table summarizes the supported conversions. Conversions * denoted by an upper-case character (i.e. <tt>'B'</tt>, <tt>'H'</tt>, * <tt>'S'</tt>, <tt>'C'</tt>, <tt>'X'</tt>, <tt>'E'</tt>, <tt>'G'</tt>, * <tt>'A'</tt>, and <tt>'T'</tt>) are the same as those for the corresponding * lower-case conversion characters except that the result is converted to * upper case according to the rules of the prevailing {@link java.util.Locale * Locale}. The result is equivalent to the following invocation of {@link * String#toUpperCase()} * * <pre> * out.toUpperCase() </pre> * * <table cellpadding=5 summary="genConv"> * * <tr><th valign="bottom"> Conversion * <th valign="bottom"> Argument Category * <th valign="bottom"> Description * * <tr><td valign="top"> <tt>'b'</tt>, <tt>'B'</tt> * <td valign="top"> general * <td> If the argument <i>arg</i> is <tt>null</tt>, then the result is * "<tt>false</tt>". If <i>arg</i> is a <tt>boolean</tt> or {@link * Boolean}, then the result is the string returned by {@link * String#valueOf(boolean) String.valueOf(arg)}. Otherwise, the result is * "true". * * <tr><td valign="top"> <tt>'h'</tt>, <tt>'H'</tt> * <td valign="top"> general * <td> If the argument <i>arg</i> is <tt>null</tt>, then the result is * "<tt>null</tt>". Otherwise, the result is obtained by invoking * <tt>Integer.toHexString(arg.hashCode())</tt>. * * <tr><td valign="top"> <tt>'s'</tt>, <tt>'S'</tt> * <td valign="top"> general * <td> If the argument <i>arg</i> is <tt>null</tt>, then the result is * "<tt>null</tt>". If <i>arg</i> implements {@link Formattable}, then * {@link Formattable#formatTo arg.formatTo} is invoked. Otherwise, the * result is obtained by invoking <tt>arg.toString()</tt>. * * <tr><td valign="top"><tt>'c'</tt>, <tt>'C'</tt> * <td valign="top"> character * <td> The result is a Unicode character * * <tr><td valign="top"><tt>'d'</tt> * <td valign="top"> integral * <td> The result is formatted as a decimal integer * * <tr><td valign="top"><tt>'o'</tt> * <td valign="top"> integral * <td> The result is formatted as an octal integer * * <tr><td valign="top"><tt>'x'</tt>, <tt>'X'</tt> * <td valign="top"> integral * <td> The result is formatted as a hexadecimal integer * * <tr><td valign="top"><tt>'e'</tt>, <tt>'E'</tt> * <td valign="top"> floating point * <td> The result is formatted as a decimal number in computerized * scientific notation * * <tr><td valign="top"><tt>'f'</tt> * <td valign="top"> floating point * <td> The result is formatted as a decimal number * * <tr><td valign="top"><tt>'g'</tt>, <tt>'G'</tt> * <td valign="top"> floating point * <td> The result is formatted using computerized scientific notation or * decimal format, depending on the precision and the value after rounding. * * <tr><td valign="top"><tt>'a'</tt>, <tt>'A'</tt> * <td valign="top"> floating point * <td> The result is formatted as a hexadecimal floating-point number with * a significand and an exponent * * <tr><td valign="top"><tt>'t'</tt>, <tt>'T'</tt> * <td valign="top"> date/time * <td> Prefix for date and time conversion characters. See <a * href="#dt">Date/Time Conversions</a>. * * <tr><td valign="top"><tt>'%'</tt> * <td valign="top"> percent * <td> The result is a literal <tt>'%'</tt> (<tt>'\u0025'</tt>) * * <tr><td valign="top"><tt>'n'</tt> * <td valign="top"> line separator * <td> The result is the platform-specific line separator * * </table> * * <p> Any characters not explicitly defined as conversions are illegal and are * reserved for future extensions. * * <h4><a name="dt">Date/Time Conversions</a></h4> * * <p> The following date and time conversion suffix characters are defined for * the <tt>'t'</tt> and <tt>'T'</tt> conversions. The types are similar to but * not completely identical to those defined by GNU <tt>date</tt> and POSIX * <tt>strftime(3c)</tt>. Additional conversion types are provided to access * Java-specific functionality (e.g. <tt>'L'</tt> for milliseconds within the * second). * * <p> The following conversion characters are used for formatting times: * * <table cellpadding=5 summary="time"> * * <tr><td valign="top"> <tt>'H'</tt> * <td> Hour of the day for the 24-hour clock, formatted as two digits with * a leading zero as necessary i.e. <tt>00 - 23</tt>. * * <tr><td valign="top"><tt>'I'</tt> * <td> Hour for the 12-hour clock, formatted as two digits with a leading * zero as necessary, i.e. <tt>01 - 12</tt>. * * <tr><td valign="top"><tt>'k'</tt> * <td> Hour of the day for the 24-hour clock, i.e. <tt>0 - 23</tt>. * * <tr><td valign="top"><tt>'l'</tt> * <td> Hour for the 12-hour clock, i.e. <tt>1 - 12</tt>. * * <tr><td valign="top"><tt>'M'</tt> * <td> Minute within the hour formatted as two digits with a leading zero * as necessary, i.e. <tt>00 - 59</tt>. * * <tr><td valign="top"><tt>'S'</tt> * <td> Seconds within the minute, formatted as two digits with a leading * zero as necessary, i.e. <tt>00 - 60</tt> ("<tt>60</tt>" is a special * value required to support leap seconds). * * <tr><td valign="top"><tt>'L'</tt> * <td> Millisecond within the second formatted as three digits with * leading zeros as necessary, i.e. <tt>000 - 999</tt>. * * <tr><td valign="top"><tt>'N'</tt> * <td> Nanosecond within the second, formatted as nine digits with leading * zeros as necessary, i.e. <tt>000000000 - 999999999</tt>. * * <tr><td valign="top"><tt>'p'</tt> * <td> Locale-specific {@linkplain * java.text.DateFormatSymbols#getAmPmStrings morning or afternoon} marker * in lower case, e.g."<tt>am</tt>" or "<tt>pm</tt>". Use of the conversion * prefix <tt>'T'</tt> forces this output to upper case. * * <tr><td valign="top"><tt>'z'</tt> * <td> <a href="http://www.ietf.org/rfc/rfc0822.txt">RFC 822</a> * style numeric time zone offset from GMT, e.g. <tt>-0800</tt>. * * <tr><td valign="top"><tt>'Z'</tt> * <td> A string representing the abbreviation for the time zone. The * Formatter's locale will supersede the locale of the argument (if any). * * <tr><td valign="top"><tt>'s'</tt> * <td> Seconds since the beginning of the epoch starting at 1 January 1970 * <tt>00:00:00</tt> UTC, i.e. <tt>Long.MIN_VALUE/1000</tt> to * <tt>Long.MAX_VALUE/1000</tt>. * * <tr><td valign="top"><tt>'Q'</tt> * <td> Milliseconds since the beginning of the epoch starting at 1 January * 1970 <tt>00:00:00</tt> UTC, i.e. <tt>Long.MIN_VALUE</tt> to * <tt>Long.MAX_VALUE</tt>. * * </table> * * <p> The following conversion characters are used for formatting dates: * * <table cellpadding=5 summary="date"> * * <tr><td valign="top"><tt>'B'</tt> * <td> Locale-specific {@linkplain java.text.DateFormatSymbols#getMonths * full month name}, e.g. <tt>"January"</tt>, <tt>"February"</tt>. * * <tr><td valign="top"><tt>'b'</tt> * <td> Locale-specific {@linkplain * java.text.DateFormatSymbols#getShortMonths abbreviated month name}, * e.g. <tt>"Jan"</tt>, <tt>"Feb"</tt>. * * <tr><td valign="top"><tt>'h'</tt> * <td> Same as <tt>'b'</tt>. * * <tr><td valign="top"><tt>'A'</tt> * <td> Locale-specific full name of the {@linkplain * java.text.DateFormatSymbols#getWeekdays day of the week}, * e.g. <tt>"Sunday"</tt>, <tt>"Monday"</tt> * * <tr><td valign="top"><tt>'a'</tt> * <td> Locale-specific short name of the {@linkplain * java.text.DateFormatSymbols#getShortWeekdays day of the week}, * e.g. <tt>"Sun"</tt>, <tt>"Mon"</tt> * * <tr><td valign="top"><tt>'C'</tt> * <td> Four-digit year divided by <tt>100</tt>, formatted as two digits * with leading zero as necessary, i.e. <tt>00 - 99</tt> * * <tr><td valign="top"><tt>'Y'</tt> * <td> Year, formatted as at least four digits with leading zeros as * necessary, e.g. <tt>0092</tt> equals <tt>92</tt> CE for the Gregorian * calendar. * * <tr><td valign="top"><tt>'y'</tt> * <td> Last two digits of the year, formatted with leading zeros as * necessary, i.e. <tt>00 - 99</tt>. * * <tr><td valign="top"><tt>'j'</tt> * <td> Day of year, formatted as three digits with leading zeros as * necessary, e.g. <tt>001 - 366</tt> for the Gregorian calendar. * * <tr><td valign="top"><tt>'m'</tt> * <td> Month, formatted as two digits with leading zeros as necessary, * i.e. <tt>01 - 13</tt>. * * <tr><td valign="top"><tt>'d'</tt> * <td> Day of month, formatted as two digits with leading zeros as * necessary, i.e. <tt>01 - 31</tt> * * <tr><td valign="top"><tt>'e'</tt> * <td> Day of month, formatted as two digits, i.e. <tt>1 - 31</tt>. * * </table> * * <p> The following conversion characters are used for formatting common * date/time compositions. * * <table cellpadding=5 summary="composites"> * * <tr><td valign="top"><tt>'R'</tt> * <td> Time formatted for the 24-hour clock as <tt>"%tH:%tM"</tt> * * <tr><td valign="top"><tt>'T'</tt> * <td> Time formatted for the 24-hour clock as <tt>"%tH:%tM:%tS"</tt>. * * <tr><td valign="top"><tt>'r'</tt> * <td> Time formatted for the 12-hour clock as <tt>"%tI:%tM:%tS %Tp"</tt>. * The location of the morning or afternoon marker (<tt>'%Tp'</tt>) may be * locale-dependent. * * <tr><td valign="top"><tt>'D'</tt> * <td> Date formatted as <tt>"%tm/%td/%ty"</tt>. * * <tr><td valign="top"><tt>'F'</tt> * <td> <a href="http://www.w3.org/TR/NOTE-datetime">ISO 8601</a> * complete date formatted as <tt>"%tY-%tm-%td"</tt>. * * <tr><td valign="top"><tt>'c'</tt> * <td> Date and time formatted as <tt>"%ta %tb %td %tT %tZ %tY"</tt>, * e.g. <tt>"Sun Jul 20 16:17:00 EDT 1969"</tt>. * * </table> * * <p> Any characters not explicitly defined as date/time conversion suffixes * are illegal and are reserved for future extensions. * * <h4> Flags </h4> * * <p> The following table summarizes the supported flags. <i>y</i> means the * flag is supported for the indicated argument types. * * <table cellpadding=5 summary="genConv"> * * <tr><th valign="bottom"> Flag <th valign="bottom"> General * <th valign="bottom"> Character <th valign="bottom"> Integral * <th valign="bottom"> Floating Point * <th valign="bottom"> Date/Time * <th valign="bottom"> Description * * <tr><td> '-' <td align="center" valign="top"> y * <td align="center" valign="top"> y * <td align="center" valign="top"> y * <td align="center" valign="top"> y * <td align="center" valign="top"> y * <td> The result will be left-justified. * * <tr><td> '#' <td align="center" valign="top"> y<sup>1</sup> * <td align="center" valign="top"> - * <td align="center" valign="top"> y<sup>3</sup> * <td align="center" valign="top"> y * <td align="center" valign="top"> - * <td> The result should use a conversion-dependent alternate form * * <tr><td> '+' <td align="center" valign="top"> - * <td align="center" valign="top"> - * <td align="center" valign="top"> y<sup>4</sup> * <td align="center" valign="top"> y * <td align="center" valign="top"> - * <td> The result will always include a sign * * <tr><td> '  ' <td align="center" valign="top"> - * <td align="center" valign="top"> - * <td align="center" valign="top"> y<sup>4</sup> * <td align="center" valign="top"> y * <td align="center" valign="top"> - * <td> The result will include a leading space for positive values * * <tr><td> '0' <td align="center" valign="top"> - * <td align="center" valign="top"> - * <td align="center" valign="top"> y * <td align="center" valign="top"> y * <td align="center" valign="top"> - * <td> The result will be zero-padded * * <tr><td> ',' <td align="center" valign="top"> - * <td align="center" valign="top"> - * <td align="center" valign="top"> y<sup>2</sup> * <td align="center" valign="top"> y<sup>5</sup> * <td align="center" valign="top"> - * <td> The result will include locale-specific {@linkplain * java.text.DecimalFormatSymbols#getGroupingSeparator grouping separators} * * <tr><td> '(' <td align="center" valign="top"> - * <td align="center" valign="top"> - * <td align="center" valign="top"> y<sup>4</sup> * <td align="center" valign="top"> y<sup>5</sup> * <td align="center"> - * <td> The result will enclose negative numbers in parentheses * * </table> * * <p> <sup>1</sup> Depends on the definition of {@link Formattable}. * * <p> <sup>2</sup> For <tt>'d'</tt> conversion only. * * <p> <sup>3</sup> For <tt>'o'</tt>, <tt>'x'</tt>, and <tt>'X'</tt> * conversions only. * * <p> <sup>4</sup> For <tt>'d'</tt>, <tt>'o'</tt>, <tt>'x'</tt>, and * <tt>'X'</tt> conversions applied to {@link java.math.BigInteger BigInteger} * or <tt>'d'</tt> applied to <tt>byte</tt>, {@link Byte}, <tt>short</tt>, {@link * Short}, <tt>int</tt> and {@link Integer}, <tt>long</tt>, and {@link Long}. * * <p> <sup>5</sup> For <tt>'e'</tt>, <tt>'E'</tt>, <tt>'f'</tt>, * <tt>'g'</tt>, and <tt>'G'</tt> conversions only. * * <p> Any characters not explicitly defined as flags are illegal and are * reserved for future extensions. * * <h4> Width </h4> * * <p> The width is the minimum number of characters to be written to the * output. For the line separator conversion, width is not applicable; if it * is provided, an exception will be thrown. * * <h4> Precision </h4> * * <p> For general argument types, the precision is the maximum number of * characters to be written to the output. * * <p> For the floating-point conversions <tt>'e'</tt>, <tt>'E'</tt>, and * <tt>'f'</tt> the precision is the number of digits after the decimal * separator. If the conversion is <tt>'g'</tt> or <tt>'G'</tt>, then the * precision is the total number of digits in the resulting magnitude after * rounding. If the conversion is <tt>'a'</tt> or <tt>'A'</tt>, then the * precision must not be specified. * * <p> For character, integral, and date/time argument types and the percent * and line separator conversions, the precision is not applicable; if a * precision is provided, an exception will be thrown. * * <h4> Argument Index </h4> * * <p> The argument index is a decimal integer indicating the position of the * argument in the argument list. The first argument is referenced by * "<tt>1$</tt>", the second by "<tt>2$</tt>", etc. * * <p> Another way to reference arguments by position is to use the * <tt>'<'</tt> (<tt>'\u003c'</tt>) flag, which causes the argument for * the previous format specifier to be re-used. For example, the following two * statements would produce identical strings: * * <blockquote><pre> * Calendar c = ...; * String s1 = String.format("Duke's Birthday: %1$tm %1$te,%1$tY", c); * * String s2 = String.format("Duke's Birthday: %1$tm %<te,%<tY", c); * </pre></blockquote> * * <hr> * <h3><a name="detail">Details</a></h3> * * <p> This section is intended to provide behavioral details for formatting, * including conditions and exceptions, supported data types, localization, and * interactions between flags, conversions, and data types. For an overview of * formatting concepts, refer to the <a href="#summary">Summary</a> * * <p> Any characters not explicitly defined as conversions, date/time * conversion suffixes, or flags are illegal and are reserved for * future extensions. Use of such a character in a format string will * cause an {@link UnknownFormatConversionException} or {@link * UnknownFormatFlagsException} to be thrown. * * <p> If the format specifier contains a width or precision with an invalid * value or which is otherwise unsupported, then a {@link * IllegalFormatWidthException} or {@link IllegalFormatPrecisionException} * respectively will be thrown. * * <p> If a format specifier contains a conversion character that is not * applicable to the corresponding argument, then an {@link * IllegalFormatConversionException} will be thrown. * * <p> All specified exceptions may be thrown by any of the <tt>format</tt> * methods of <tt>Formatter</tt> as well as by any <tt>format</tt> convenience * methods such as {@link String#format(String,Object...) String.format} and * {@link java.io.PrintStream#printf(String,Object...) PrintStream.printf}. * * <p> Conversions denoted by an upper-case character (i.e. <tt>'B'</tt>, * <tt>'H'</tt>, <tt>'S'</tt>, <tt>'C'</tt>, <tt>'X'</tt>, <tt>'E'</tt>, * <tt>'G'</tt>, <tt>'A'</tt>, and <tt>'T'</tt>) are the same as those for the * corresponding lower-case conversion characters except that the result is * converted to upper case according to the rules of the prevailing {@link * java.util.Locale Locale}. The result is equivalent to the following * invocation of {@link String#toUpperCase()} * * <pre> * out.toUpperCase() </pre> * * <h4><a name="dgen">General</a></h4> * * <p> The following general conversions may be applied to any argument type: * * <table cellpadding=5 summary="dgConv"> * * <tr><td valign="top"> <tt>'b'</tt> * <td valign="top"> <tt>'\u0062'</tt> * <td> Produces either "<tt>true</tt>" or "<tt>false</tt>" as returned by * {@link Boolean#toString(boolean)}. * * <p> If the argument is <tt>null</tt>, then the result is * "<tt>false</tt>". If the argument is a <tt>boolean</tt> or {@link * Boolean}, then the result is the string returned by {@link * String#valueOf(boolean) String.valueOf()}. Otherwise, the result is * "<tt>true</tt>". * * <p> If the <tt>'#'</tt> flag is given, then a {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'B'</tt> * <td valign="top"> <tt>'\u0042'</tt> * <td> The upper-case variant of <tt>'b'</tt>. * * <tr><td valign="top"> <tt>'h'</tt> * <td valign="top"> <tt>'\u0068'</tt> * <td> Produces a string representing the hash code value of the object. * * <p> If the argument, <i>arg</i> is <tt>null</tt>, then the * result is "<tt>null</tt>". Otherwise, the result is obtained * by invoking <tt>Integer.toHexString(arg.hashCode())</tt>. * * <p> If the <tt>'#'</tt> flag is given, then a {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'H'</tt> * <td valign="top"> <tt>'\u0048'</tt> * <td> The upper-case variant of <tt>'h'</tt>. * * <tr><td valign="top"> <tt>'s'</tt> * <td valign="top"> <tt>'\u0073'</tt> * <td> Produces a string. * * <p> If the argument is <tt>null</tt>, then the result is * "<tt>null</tt>". If the argument implements {@link Formattable}, then * its {@link Formattable#formatTo formatTo} method is invoked. * Otherwise, the result is obtained by invoking the argument's * <tt>toString()</tt> method. * * <p> If the <tt>'#'</tt> flag is given and the argument is not a {@link * Formattable} , then a {@link FormatFlagsConversionMismatchException} * will be thrown. * * <tr><td valign="top"> <tt>'S'</tt> * <td valign="top"> <tt>'\u0053'</tt> * <td> The upper-case variant of <tt>'s'</tt>. * * </table> * * <p> The following <a name="dFlags">flags</a> apply to general conversions: * * <table cellpadding=5 summary="dFlags"> * * <tr><td valign="top"> <tt>'-'</tt> * <td valign="top"> <tt>'\u002d'</tt> * <td> Left justifies the output. Spaces (<tt>'\u0020'</tt>) will be * added at the end of the converted value as required to fill the minimum * width of the field. If the width is not provided, then a {@link * MissingFormatWidthException} will be thrown. If this flag is not given * then the output will be right-justified. * * <tr><td valign="top"> <tt>'#'</tt> * <td valign="top"> <tt>'\u0023'</tt> * <td> Requires the output use an alternate form. The definition of the * form is specified by the conversion. * * </table> * * <p> The <a name="genWidth">width</a> is the minimum number of characters to * be written to the * output. If the length of the converted value is less than the width then * the output will be padded by <tt>'  '</tt> (<tt>\u0020'</tt>) * until the total number of characters equals the width. The padding is on * the left by default. If the <tt>'-'</tt> flag is given, then the padding * will be on the right. If the width is not specified then there is no * minimum. * * <p> The precision is the maximum number of characters to be written to the * output. The precision is applied before the width, thus the output will be * truncated to <tt>precision</tt> characters even if the width is greater than * the precision. If the precision is not specified then there is no explicit * limit on the number of characters. * * <h4><a name="dchar">Character</a></h4> * * This conversion may be applied to <tt>char</tt> and {@link Character}. It * may also be applied to the types <tt>byte</tt>, {@link Byte}, * <tt>short</tt>, and {@link Short}, <tt>int</tt> and {@link Integer} when * {@link Character#isValidCodePoint} returns <tt>true</tt>. If it returns * <tt>false</tt> then an {@link IllegalFormatCodePointException} will be * thrown. * * <table cellpadding=5 summary="charConv"> * * <tr><td valign="top"> <tt>'c'</tt> * <td valign="top"> <tt>'\u0063'</tt> * <td> Formats the argument as a Unicode character as described in <a * href="../lang/Character.html#unicode">Unicode Character * Representation</a>. This may be more than one 16-bit <tt>char</tt> in * the case where the argument represents a supplementary character. * * <p> If the <tt>'#'</tt> flag is given, then a {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'C'</tt> * <td valign="top"> <tt>'\u0043'</tt> * <td> The upper-case variant of <tt>'c'</tt>. * * </table> * * <p> The <tt>'-'</tt> flag defined for <a href="#dFlags">General * conversions</a> applies. If the <tt>'#'</tt> flag is given, then a {@link * FormatFlagsConversionMismatchException} will be thrown. * * <p> The width is defined as for <a href="#genWidth">General conversions</a>. * * <p> The precision is not applicable. If the precision is specified then an * {@link IllegalFormatPrecisionException} will be thrown. * * <h4><a name="dnum">Numeric</a></h4> * * <p> Numeric conversions are divided into the following categories: * * <ol> * * <li> <a href="#dnint"><b>Byte, Short, Integer, and Long</b></a> * * <li> <a href="#dnbint"><b>BigInteger</b></a> * * <li> <a href="#dndec"><b>Float and Double</b></a> * * <li> <a href="#dndec"><b>BigDecimal</b></a> * * </ol> * * <p> Numeric types will be formatted according to the following algorithm: * * <p><b><a name="l10n algorithm"> Number Localization Algorithm</a></b> * * <p> After digits are obtained for the integer part, fractional part, and * exponent (as appropriate for the data type), the following transformation * is applied: * * <ol> * * <li> Each digit character <i>d</i> in the string is replaced by a * locale-specific digit computed relative to the current locale's * {@linkplain java.text.DecimalFormatSymbols#getZeroDigit() zero digit} * <i>z</i>; that is <i>d - </i> <tt>'0'</tt> * <i> + z</i>. * * <li> If a decimal separator is present, a locale-specific {@linkplain * java.text.DecimalFormatSymbols#getDecimalSeparator decimal separator} is * substituted. * * <li> If the <tt>','</tt> (<tt>'\u002c'</tt>) * <a name="l10n group">flag</a> is given, then the locale-specific {@linkplain * java.text.DecimalFormatSymbols#getGroupingSeparator grouping separator} is * inserted by scanning the integer part of the string from least significant * to most significant digits and inserting a separator at intervals defined by * the locale's {@linkplain java.text.DecimalFormat#getGroupingSize() grouping * size}. * * <li> If the <tt>'0'</tt> flag is given, then the locale-specific {@linkplain * java.text.DecimalFormatSymbols#getZeroDigit() zero digits} are inserted * after the sign character, if any, and before the first non-zero digit, until * the length of the string is equal to the requested field width. * * <li> If the value is negative and the <tt>'('</tt> flag is given, then a * <tt>'('</tt> (<tt>'\u0028'</tt>) is prepended and a <tt>')'</tt> * (<tt>'\u0029'</tt>) is appended. * * <li> If the value is negative (or floating-point negative zero) and * <tt>'('</tt> flag is not given, then a <tt>'-'</tt> (<tt>'\u002d'</tt>) * is prepended. * * <li> If the <tt>'+'</tt> flag is given and the value is positive or zero (or * floating-point positive zero), then a <tt>'+'</tt> (<tt>'\u002b'</tt>) * will be prepended. * * </ol> * * <p> If the value is NaN or positive infinity the literal strings "NaN" or * "Infinity" respectively, will be output. If the value is negative infinity, * then the output will be "(Infinity)" if the <tt>'('</tt> flag is given * otherwise the output will be "-Infinity". These values are not localized. * * <p><a name="dnint"><b> Byte, Short, Integer, and Long </b></a> * * <p> The following conversions may be applied to <tt>byte</tt>, {@link Byte}, * <tt>short</tt>, {@link Short}, <tt>int</tt> and {@link Integer}, * <tt>long</tt>, and {@link Long}. * * <table cellpadding=5 summary="IntConv"> * * <tr><td valign="top"> <tt>'d'</tt> * <td valign="top"> <tt>'\u0054'</tt> * <td> Formats the argument as a decimal integer. The <a * href="#l10n algorithm">localization algorithm</a> is applied. * * <p> If the <tt>'0'</tt> flag is given and the value is negative, then * the zero padding will occur after the sign. * * <p> If the <tt>'#'</tt> flag is given then a {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'o'</tt> * <td valign="top"> <tt>'\u006f'</tt> * <td> Formats the argument as an integer in base eight. No localization * is applied. * * <p> If <i>x</i> is negative then the result will be an unsigned value * generated by adding 2<sup>n</sup> to the value where <tt>n</tt> is the * number of bits in the type as returned by the static <tt>SIZE</tt> field * in the {@linkplain Byte#SIZE Byte}, {@linkplain Short#SIZE Short}, * {@linkplain Integer#SIZE Integer}, or {@linkplain Long#SIZE Long} * classes as appropriate. * * <p> If the <tt>'#'</tt> flag is given then the output will always begin * with the radix indicator <tt>'0'</tt>. * * <p> If the <tt>'0'</tt> flag is given then the output will be padded * with leading zeros to the field width following any indication of sign. * * <p> If <tt>'('</tt>, <tt>'+'</tt>, '  ', or <tt>','</tt> flags * are given then a {@link FormatFlagsConversionMismatchException} will be * thrown. * * <tr><td valign="top"> <tt>'x'</tt> * <td valign="top"> <tt>'\u0078'</tt> * <td> Formats the argument as an integer in base sixteen. No * localization is applied. * * <p> If <i>x</i> is negative then the result will be an unsigned value * generated by adding 2<sup>n</sup> to the value where <tt>n</tt> is the * number of bits in the type as returned by the static <tt>SIZE</tt> field * in the {@linkplain Byte#SIZE Byte}, {@linkplain Short#SIZE Short}, * {@linkplain Integer#SIZE Integer}, or {@linkplain Long#SIZE Long} * classes as appropriate. * * <p> If the <tt>'#'</tt> flag is given then the output will always begin * with the radix indicator <tt>"0x"</tt>. * * <p> If the <tt>'0'</tt> flag is given then the output will be padded to * the field width with leading zeros after the radix indicator or sign (if * present). * * <p> If <tt>'('</tt>, <tt>'  '</tt>, <tt>'+'</tt>, or * <tt>','</tt> flags are given then a {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'X'</tt> * <td valign="top"> <tt>'\u0058'</tt> * <td> The upper-case variant of <tt>'x'</tt>. The entire string * representing the number will be converted to {@linkplain * String#toUpperCase upper case} including the <tt>'x'</tt> (if any) and * all hexadecimal digits <tt>'a'</tt> - <tt>'f'</tt> * (<tt>'\u0061'</tt> - <tt>'\u0066'</tt>). * * </table> * * <p> If the conversion is <tt>'o'</tt>, <tt>'x'</tt>, or <tt>'X'</tt> and * both the <tt>'#'</tt> and the <tt>'0'</tt> flags are given, then result will * contain the radix indicator (<tt>'0'</tt> for octal and <tt>"0x"</tt> or * <tt>"0X"</tt> for hexadecimal), some number of zeros (based on the width), * and the value. * * <p> If the <tt>'-'</tt> flag is not given, then the space padding will occur * before the sign. * * <p> The following <a name="intFlags">flags</a> apply to numeric integral * conversions: * * <table cellpadding=5 summary="intFlags"> * * <tr><td valign="top"> <tt>'+'</tt> * <td valign="top"> <tt>'\u002b'</tt> * <td> Requires the output to include a positive sign for all positive * numbers. If this flag is not given then only negative values will * include a sign. * * <p> If both the <tt>'+'</tt> and <tt>'  '</tt> flags are given * then an {@link IllegalFormatFlagsException} will be thrown. * * <tr><td valign="top"> <tt>'  '</tt> * <td valign="top"> <tt>'\u0020'</tt> * <td> Requires the output to include a single extra space * (<tt>'\u0020'</tt>) for non-negative values. * * <p> If both the <tt>'+'</tt> and <tt>'  '</tt> flags are given * then an {@link IllegalFormatFlagsException} will be thrown. * * <tr><td valign="top"> <tt>'0'</tt> * <td valign="top"> <tt>'\u0030'</tt> * <td> Requires the output to be padded with leading {@linkplain * java.text.DecimalFormatSymbols#getZeroDigit zeros} to the minimum field * width following any sign or radix indicator except when converting NaN * or infinity. If the width is not provided, then a {@link * MissingFormatWidthException} will be thrown. * * <p> If both the <tt>'-'</tt> and <tt>'0'</tt> flags are given then an * {@link IllegalFormatFlagsException} will be thrown. * * <tr><td valign="top"> <tt>','</tt> * <td valign="top"> <tt>'\u002c'</tt> * <td> Requires the output to include the locale-specific {@linkplain * java.text.DecimalFormatSymbols#getGroupingSeparator group separators} as * described in the <a href="#l10n group">"group" section</a> of the * localization algorithm. * * <tr><td valign="top"> <tt>'('</tt> * <td valign="top"> <tt>'\u0028'</tt> * <td> Requires the output to prepend a <tt>'('</tt> * (<tt>'\u0028'</tt>) and append a <tt>')'</tt> * (<tt>'\u0029'</tt>) to negative values. * * </table> * * <p> If no <a name="intdFlags">flags</a> are given the default formatting is * as follows: * * <ul> * * <li> The output is right-justified within the <tt>width</tt> * * <li> Negative numbers begin with a <tt>'-'</tt> (<tt>'\u002d'</tt>) * * <li> Positive numbers and zero do not include a sign or extra leading * space * * <li> No grouping separators are included * * </ul> * * <p> The <a name="intWidth">width</a> is the minimum number of characters to * be written to the output. This includes any signs, digits, grouping * separators, radix indicator, and parentheses. If the length of the * converted value is less than the width then the output will be padded by * spaces (<tt>'\u0020'</tt>) until the total number of characters equals * width. The padding is on the left by default. If <tt>'-'</tt> flag is * given then the padding will be on the right. If width is not specified then * there is no minimum. * * <p> The precision is not applicable. If precision is specified then an * {@link IllegalFormatPrecisionException} will be thrown. * * <p><a name="dnbint"><b> BigInteger </b></a> * * <p> The following conversions may be applied to {@link * java.math.BigInteger}. * * <table cellpadding=5 summary="BIntConv"> * * <tr><td valign="top"> <tt>'d'</tt> * <td valign="top"> <tt>'\u0054'</tt> * <td> Requires the output to be formatted as a decimal integer. The <a * href="#l10n algorithm">localization algorithm</a> is applied. * * <p> If the <tt>'#'</tt> flag is given {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'o'</tt> * <td valign="top"> <tt>'\u006f'</tt> * <td> Requires the output to be formatted as an integer in base eight. * No localization is applied. * * <p> If <i>x</i> is negative then the result will be a signed value * beginning with <tt>'-'</tt> (<tt>'\u002d'</tt>). Signed output is * allowed for this type because unlike the primitive types it is not * possible to create an unsigned equivalent without assuming an explicit * data-type size. * * <p> If <i>x</i> is positive or zero and the <tt>'+'</tt> flag is given * then the result will begin with <tt>'+'</tt> (<tt>'\u002b'</tt>). * * <p> If the <tt>'#'</tt> flag is given then the output will always begin * with <tt>'0'</tt> prefix. * * <p> If the <tt>'0'</tt> flag is given then the output will be padded * with leading zeros to the field width following any indication of sign. * * <p> If the <tt>','</tt> flag is given then a {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'x'</tt> * <td valign="top"> <tt>'\u0078'</tt> * <td> Requires the output to be formatted as an integer in base * sixteen. No localization is applied. * * <p> If <i>x</i> is negative then the result will be a signed value * beginning with <tt>'-'</tt> (<tt>'\u002d'</tt>). Signed output is * allowed for this type because unlike the primitive types it is not * possible to create an unsigned equivalent without assuming an explicit * data-type size. * * <p> If <i>x</i> is positive or zero and the <tt>'+'</tt> flag is given * then the result will begin with <tt>'+'</tt> (<tt>'\u002b'</tt>). * * <p> If the <tt>'#'</tt> flag is given then the output will always begin * with the radix indicator <tt>"0x"</tt>. * * <p> If the <tt>'0'</tt> flag is given then the output will be padded to * the field width with leading zeros after the radix indicator or sign (if * present). * * <p> If the <tt>','</tt> flag is given then a {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'X'</tt> * <td valign="top"> <tt>'\u0058'</tt> * <td> The upper-case variant of <tt>'x'</tt>. The entire string * representing the number will be converted to {@linkplain * String#toUpperCase upper case} including the <tt>'x'</tt> (if any) and * all hexadecimal digits <tt>'a'</tt> - <tt>'f'</tt> * (<tt>'\u0061'</tt> - <tt>'\u0066'</tt>). * * </table> * * <p> If the conversion is <tt>'o'</tt>, <tt>'x'</tt>, or <tt>'X'</tt> and * both the <tt>'#'</tt> and the <tt>'0'</tt> flags are given, then result will * contain the base indicator (<tt>'0'</tt> for octal and <tt>"0x"</tt> or * <tt>"0X"</tt> for hexadecimal), some number of zeros (based on the width), * and the value. * * <p> If the <tt>'0'</tt> flag is given and the value is negative, then the * zero padding will occur after the sign. * * <p> If the <tt>'-'</tt> flag is not given, then the space padding will occur * before the sign. * * <p> All <a href="#intFlags">flags</a> defined for Byte, Short, Integer, and * Long apply. The <a href="#intdFlags">default behavior</a> when no flags are * given is the same as for Byte, Short, Integer, and Long. * * <p> The specification of <a href="#intWidth">width</a> is the same as * defined for Byte, Short, Integer, and Long. * * <p> The precision is not applicable. If precision is specified then an * {@link IllegalFormatPrecisionException} will be thrown. * * <p><a name="dndec"><b> Float and Double</b></a> * * <p> The following conversions may be applied to <tt>float</tt>, {@link * Float}, <tt>double</tt> and {@link Double}. * * <table cellpadding=5 summary="floatConv"> * * <tr><td valign="top"> <tt>'e'</tt> * <td valign="top"> <tt>'\u0065'</tt> * <td> Requires the output to be formatted using <a * name="scientific">computerized scientific notation</a>. The <a * href="#l10n algorithm">localization algorithm</a> is applied. * * <p> The formatting of the magnitude <i>m</i> depends upon its value. * * <p> If <i>m</i> is NaN or infinite, the literal strings "NaN" or * "Infinity", respectively, will be output. These values are not * localized. * * <p> If <i>m</i> is positive-zero or negative-zero, then the exponent * will be <tt>"+00"</tt>. * * <p> Otherwise, the result is a string that represents the sign and * magnitude (absolute value) of the argument. The formatting of the sign * is described in the <a href="#l10n algorithm">localization * algorithm</a>. The formatting of the magnitude <i>m</i> depends upon its * value. * * <p> Let <i>n</i> be the unique integer such that 10<sup><i>n</i></sup> * <= <i>m</i> < 10<sup><i>n</i>+1</sup>; then let <i>a</i> be the * mathematically exact quotient of <i>m</i> and 10<sup><i>n</i></sup> so * that 1 <= <i>a</i> < 10. The magnitude is then represented as the * integer part of <i>a</i>, as a single decimal digit, followed by the * decimal separator followed by decimal digits representing the fractional * part of <i>a</i>, followed by the exponent symbol <tt>'e'</tt> * (<tt>'\u0065'</tt>), followed by the sign of the exponent, followed * by a representation of <i>n</i> as a decimal integer, as produced by the * method {@link Long#toString(long, int)}, and zero-padded to include at * least two digits. * * <p> The number of digits in the result for the fractional part of * <i>m</i> or <i>a</i> is equal to the precision. If the precision is not * specified then the default value is <tt>6</tt>. If the precision is less * than the number of digits which would appear after the decimal point in * the string returned by {@link Float#toString(float)} or {@link * Double#toString(double)} respectively, then the value will be rounded * using the {@linkplain java.math.BigDecimal#ROUND_HALF_UP round half up * algorithm}. Otherwise, zeros may be appended to reach the precision. * For a canonical representation of the value, use {@link * Float#toString(float)} or {@link Double#toString(double)} as * appropriate. * * <p>If the <tt>','</tt> flag is given, then an {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'E'</tt> * <td valign="top"> <tt>'\u0045'</tt> * <td> The upper-case variant of <tt>'e'</tt>. The exponent symbol * will be <tt>'E'</tt> (<tt>'\u0045'</tt>). * * <tr><td valign="top"> <tt>'g'</tt> * <td valign="top"> <tt>'\u0067'</tt> * <td> Requires the output to be formatted in general scientific notation * as described below. The <a href="#l10n algorithm">localization * algorithm</a> is applied. * * <p> After rounding for the precision, the formatting of the resulting * magnitude <i>m</i> depends on its value. * * <p> If <i>m</i> is greater than or equal to 10<sup>-4</sup> but less * than 10<sup>precision</sup> then it is represented in <i><a * href="#decimal">decimal format</a></i>. * * <p> If <i>m</i> is less than 10<sup>-4</sup> or greater than or equal to * 10<sup>precision</sup>, then it is represented in <i><a * href="#scientific">computerized scientific notation</a></i>. * * <p> The total number of significant digits in <i>m</i> is equal to the * precision. If the precision is not specified, then the default value is * <tt>6</tt>. If the precision is <tt>0</tt>, then it is taken to be * <tt>1</tt>. * * <p> If the <tt>'#'</tt> flag is given then an {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'G'</tt> * <td valign="top"> <tt>'\u0047'</tt> * <td> The upper-case variant of <tt>'g'</tt>. * * <tr><td valign="top"> <tt>'f'</tt> * <td valign="top"> <tt>'\u0066'</tt> * <td> Requires the output to be formatted using <a name="decimal">decimal * format</a>. The <a href="#l10n algorithm">localization algorithm</a> is * applied. * * <p> The result is a string that represents the sign and magnitude * (absolute value) of the argument. The formatting of the sign is * described in the <a href="#l10n algorithm">localization * algorithm</a>. The formatting of the magnitude <i>m</i> depends upon its * value. * * <p> If <i>m</i> NaN or infinite, the literal strings "NaN" or * "Infinity", respectively, will be output. These values are not * localized. * * <p> The magnitude is formatted as the integer part of <i>m</i>, with no * leading zeroes, followed by the decimal separator followed by one or * more decimal digits representing the fractional part of <i>m</i>. * * <p> The number of digits in the result for the fractional part of * <i>m</i> or <i>a</i> is equal to the precision. If the precision is not * specified then the default value is <tt>6</tt>. If the precision is less * than the number of digits which would appear after the decimal point in * the string returned by {@link Float#toString(float)} or {@link * Double#toString(double)} respectively, then the value will be rounded * using the {@linkplain java.math.BigDecimal#ROUND_HALF_UP round half up * algorithm}. Otherwise, zeros may be appended to reach the precision. * For a canonical representation of the value,use {@link * Float#toString(float)} or {@link Double#toString(double)} as * appropriate. * * <tr><td valign="top"> <tt>'a'</tt> * <td valign="top"> <tt>'\u0061'</tt> * <td> Requires the output to be formatted in hexadecimal exponential * form. No localization is applied. * * <p> The result is a string that represents the sign and magnitude * (absolute value) of the argument <i>x</i>. * * <p> If <i>x</i> is negative or a negative-zero value then the result * will begin with <tt>'-'</tt> (<tt>'\u002d'</tt>). * * <p> If <i>x</i> is positive or a positive-zero value and the * <tt>'+'</tt> flag is given then the result will begin with <tt>'+'</tt> * (<tt>'\u002b'</tt>). * * <p> The formatting of the magnitude <i>m</i> depends upon its value. * * <ul> * * <li> If the value is NaN or infinite, the literal strings "NaN" or * "Infinity", respectively, will be output. * * <li> If <i>m</i> is zero then it is represented by the string * <tt>"0x0.0p0"</tt>. * * <li> If <i>m</i> is a <tt>double</tt> value with a normalized * representation then substrings are used to represent the significand and * exponent fields. The significand is represented by the characters * <tt>"0x1."</tt> followed by the hexadecimal representation of the rest * of the significand as a fraction. The exponent is represented by * <tt>'p'</tt> (<tt>'\u0070'</tt>) followed by a decimal string of the * unbiased exponent as if produced by invoking {@link * Integer#toString(int) Integer.toString} on the exponent value. * * <li> If <i>m</i> is a <tt>double</tt> value with a subnormal * representation then the significand is represented by the characters * <tt>'0x0.'</tt> followed by the hexadecimal representation of the rest * of the significand as a fraction. The exponent is represented by * <tt>'p-1022'</tt>. Note that there must be at least one nonzero digit * in a subnormal significand. * * </ul> * * <p> If the <tt>'('</tt> or <tt>','</tt> flags are given, then a {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'A'</tt> * <td valign="top"> <tt>'\u0041'</tt> * <td> The upper-case variant of <tt>'a'</tt>. The entire string * representing the number will be converted to upper case including the * <tt>'x'</tt> (<tt>'\u0078'</tt>) and <tt>'p'</tt> * (<tt>'\u0070'</tt> and all hexadecimal digits <tt>'a'</tt> - * <tt>'f'</tt> (<tt>'\u0061'</tt> - <tt>'\u0066'</tt>). * * </table> * * <p> All <a href="#intFlags">flags</a> defined for Byte, Short, Integer, and * Long apply. * * <p> If the <tt>'#'</tt> flag is given, then the decimal separator will * always be present. * * <p> If no <a name="floatdFlags">flags</a> are given the default formatting * is as follows: * * <ul> * * <li> The output is right-justified within the <tt>width</tt> * * <li> Negative numbers begin with a <tt>'-'</tt> * * <li> Positive numbers and positive zero do not include a sign or extra * leading space * * <li> No grouping separators are included * * <li> The decimal separator will only appear if a digit follows it * * </ul> * * <p> The <a name="floatDWidth">width</a> is the minimum number of characters * to be written to the output. This includes any signs, digits, grouping * separators, decimal separators, exponential symbol, radix indicator, * parentheses, and strings representing infinity and NaN as applicable. If * the length of the converted value is less than the width then the output * will be padded by spaces (<tt>'\u0020'</tt>) until the total number of * characters equals width. The padding is on the left by default. If the * <tt>'-'</tt> flag is given then the padding will be on the right. If width * is not specified then there is no minimum. * * <p> If the <a name="floatDPrec">conversion</a> is <tt>'e'</tt>, * <tt>'E'</tt> or <tt>'f'</tt>, then the precision is the number of digits * after the decimal separator. If the precision is not specified, then it is * assumed to be <tt>6</tt>. * * <p> If the conversion is <tt>'g'</tt> or <tt>'G'</tt>, then the precision is * the total number of significant digits in the resulting magnitude after * rounding. If the precision is not specified, then the default value is * <tt>6</tt>. If the precision is <tt>0</tt>, then it is taken to be * <tt>1</tt>. * * <p> If the conversion is <tt>'a'</tt> or <tt>'A'</tt>, then the precision * is the number of hexadecimal digits after the decimal separator. If the * precision is not provided, then all of the digits as returned by {@link * Double#toHexString(double)} will be output. * * <p><a name="dndec"><b> BigDecimal </b></a> * * <p> The following conversions may be applied {@link java.math.BigDecimal * BigDecimal}. * * <table cellpadding=5 summary="floatConv"> * * <tr><td valign="top"> <tt>'e'</tt> * <td valign="top"> <tt>'\u0065'</tt> * <td> Requires the output to be formatted using <a * name="scientific">computerized scientific notation</a>. The <a * href="#l10n algorithm">localization algorithm</a> is applied. * * <p> The formatting of the magnitude <i>m</i> depends upon its value. * * <p> If <i>m</i> is positive-zero or negative-zero, then the exponent * will be <tt>"+00"</tt>. * * <p> Otherwise, the result is a string that represents the sign and * magnitude (absolute value) of the argument. The formatting of the sign * is described in the <a href="#l10n algorithm">localization * algorithm</a>. The formatting of the magnitude <i>m</i> depends upon its * value. * * <p> Let <i>n</i> be the unique integer such that 10<sup><i>n</i></sup> * <= <i>m</i> < 10<sup><i>n</i>+1</sup>; then let <i>a</i> be the * mathematically exact quotient of <i>m</i> and 10<sup><i>n</i></sup> so * that 1 <= <i>a</i> < 10. The magnitude is then represented as the * integer part of <i>a</i>, as a single decimal digit, followed by the * decimal separator followed by decimal digits representing the fractional * part of <i>a</i>, followed by the exponent symbol <tt>'e'</tt> * (<tt>'\u0065'</tt>), followed by the sign of the exponent, followed * by a representation of <i>n</i> as a decimal integer, as produced by the * method {@link Long#toString(long, int)}, and zero-padded to include at * least two digits. * * <p> The number of digits in the result for the fractional part of * <i>m</i> or <i>a</i> is equal to the precision. If the precision is not * specified then the default value is <tt>6</tt>. If the precision is * less than the number of digits which would appear after the decimal * point in the string returned by {@link Float#toString(float)} or {@link * Double#toString(double)} respectively, then the value will be rounded * using the {@linkplain java.math.BigDecimal#ROUND_HALF_UP round half up * algorithm}. Otherwise, zeros may be appended to reach the precision. * For a canonical representation of the value, use {@link * BigDecimal#toString()}. * * <p> If the <tt>','</tt> flag is given, then an {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'E'</tt> * <td valign="top"> <tt>'\u0045'</tt> * <td> The upper-case variant of <tt>'e'</tt>. The exponent symbol * will be <tt>'E'</tt> (<tt>'\u0045'</tt>). * * <tr><td valign="top"> <tt>'g'</tt> * <td valign="top"> <tt>'\u0067'</tt> * <td> Requires the output to be formatted in general scientific notation * as described below. The <a href="#l10n algorithm">localization * algorithm</a> is applied. * * <p> After rounding for the precision, the formatting of the resulting * magnitude <i>m</i> depends on its value. * * <p> If <i>m</i> is greater than or equal to 10<sup>-4</sup> but less * than 10<sup>precision</sup> then it is represented in <i><a * href="#decimal">decimal format</a></i>. * * <p> If <i>m</i> is less than 10<sup>-4</sup> or greater than or equal to * 10<sup>precision</sup>, then it is represented in <i><a * href="#scientific">computerized scientific notation</a></i>. * * <p> The total number of significant digits in <i>m</i> is equal to the * precision. If the precision is not specified, then the default value is * <tt>6</tt>. If the precision is <tt>0</tt>, then it is taken to be * <tt>1</tt>. * * <p> If the <tt>'#'</tt> flag is given then an {@link * FormatFlagsConversionMismatchException} will be thrown. * * <tr><td valign="top"> <tt>'G'</tt> * <td valign="top"> <tt>'\u0047'</tt> * <td> The upper-case variant of <tt>'g'</tt>. * * <tr><td valign="top"> <tt>'f'</tt> * <td valign="top"> <tt>'\u0066'</tt> * <td> Requires the output to be formatted using <a name="decimal">decimal * format</a>. The <a href="#l10n algorithm">localization algorithm</a> is * applied. * * <p> The result is a string that represents the sign and magnitude * (absolute value) of the argument. The formatting of the sign is * described in the <a href="#l10n algorithm">localization * algorithm</a>. The formatting of the magnitude <i>m</i> depends upon its * value. * * <p> The magnitude is formatted as the integer part of <i>m</i>, with no * leading zeroes, followed by the decimal separator followed by one or * more decimal digits representing the fractional part of <i>m</i>. * * <p> The number of digits in the result for the fractional part of * <i>m</i> or <i>a</i> is equal to the precision. If the precision is not * specified then the default value is <tt>6</tt>. If the precision is * less than the number of digits which would appear after the decimal * point in the string returned by {@link Float#toString(float)} or {@link * Double#toString(double)} respectively, then the value will be rounded * using the {@linkplain java.math.BigDecimal#ROUND_HALF_UP round half up * algorithm}. Otherwise, zeros may be appended to reach the precision. * For a canonical representation of the value, use {@link * BigDecimal#toString()}. * * </table> * * <p> All <a href="#intFlags">flags</a> defined for Byte, Short, Integer, and * Long apply. * * <p> If the <tt>'#'</tt> flag is given, then the decimal separator will * always be present. * * <p> The <a href="#floatdFlags">default behavior</a> when no flags are * given is the same as for Float and Double. * * <p> The specification of <a href="#floatDWidth">width</a> and <a * href="#floatDPrec">precision</a> is the same as defined for Float and * Double. * * <h4><a name="ddt">Date/Time</a></h4> * * <p> This conversion may be applied to <tt>long</tt>, {@link Long}, {@link * Calendar}, and {@link Date}. * * <table cellpadding=5 summary="DTConv"> * * <tr><td valign="top"> <tt>'t'</tt> * <td valign="top"> <tt>'\u0074'</tt> * <td> Prefix for date and time conversion characters. * <tr><td valign="top"> <tt>'T'</tt> * <td valign="top"> <tt>'\u0054'</tt> * <td> The upper-case variant of <tt>'t'</tt>. * * </table> * * <p> The following date and time conversion character suffixes are defined * for the <tt>'t'</tt> and <tt>'T'</tt> conversions. The types are similar to * but not completely identical to those defined by GNU <tt>date</tt> and * POSIX <tt>strftime(3c)</tt>. Additional conversion types are provided to * access Java-specific functionality (e.g. <tt>'L'</tt> for milliseconds * within the second). * * <p> The following conversion characters are used for formatting times: * * <table cellpadding=5 summary="time"> * * <tr><td valign="top"> <tt>'H'</tt> * <td valign="top"> <tt>'\u0048'</tt> * <td> Hour of the day for the 24-hour clock, formatted as two digits with * a leading zero as necessary i.e. <tt>00 - 23</tt>. <tt>00</tt> * corresponds to midnight. * * <tr><td valign="top"><tt>'I'</tt> * <td valign="top"> <tt>'\u0049'</tt> * <td> Hour for the 12-hour clock, formatted as two digits with a leading * zero as necessary, i.e. <tt>01 - 12</tt>. <tt>01</tt> corresponds to * one o'clock (either morning or afternoon). * * <tr><td valign="top"><tt>'k'</tt> * <td valign="top"> <tt>'\u006b'</tt> * <td> Hour of the day for the 24-hour clock, i.e. <tt>0 - 23</tt>. * <tt>0</tt> corresponds to midnight. * * <tr><td valign="top"><tt>'l'</tt> * <td valign="top"> <tt>'\u006c'</tt> * <td> Hour for the 12-hour clock, i.e. <tt>1 - 12</tt>. <tt>1</tt> * corresponds to one o'clock (either morning or afternoon). * * <tr><td valign="top"><tt>'M'</tt> * <td valign="top"> <tt>'\u004d'</tt> * <td> Minute within the hour formatted as two digits with a leading zero * as necessary, i.e. <tt>00 - 59</tt>. * * <tr><td valign="top"><tt>'S'</tt> * <td valign="top"> <tt>'\u0053'</tt> * <td> Seconds within the minute, formatted as two digits with a leading * zero as necessary, i.e. <tt>00 - 60</tt> ("<tt>60</tt>" is a special * value required to support leap seconds). * * <tr><td valign="top"><tt>'L'</tt> * <td valign="top"> <tt>'\u004c'</tt> * <td> Millisecond within the second formatted as three digits with * leading zeros as necessary, i.e. <tt>000 - 999</tt>. * * <tr><td valign="top"><tt>'N'</tt> * <td valign="top"> <tt>'\u004e'</tt> * <td> Nanosecond within the second, formatted as nine digits with leading * zeros as necessary, i.e. <tt>000000000 - 999999999</tt>. The precision * of this value is limited by the resolution of the underlying operating * system or hardware. * * <tr><td valign="top"><tt>'p'</tt> * <td valign="top"> <tt>'\u0070'</tt> * <td> Locale-specific {@linkplain * java.text.DateFormatSymbols#getAmPmStrings morning or afternoon} marker * in lower case, e.g."<tt>am</tt>" or "<tt>pm</tt>". Use of the * conversion prefix <tt>'T'</tt> forces this output to upper case. (Note * that <tt>'p'</tt> produces lower-case output. This is different from * GNU <tt>date</tt> and POSIX <tt>strftime(3c)</tt> which produce * upper-case output.) * * <tr><td valign="top"><tt>'z'</tt> * <td valign="top"> <tt>'\u007a'</tt> * <td> <a href="http://www.ietf.org/rfc/rfc0822.txt">RFC 822</a> * style numeric time zone offset from GMT, e.g. <tt>-0800</tt>. * * <tr><td valign="top"><tt>'Z'</tt> * <td valign="top"> <tt>'\u005a'</tt> * <td> A string representing the abbreviation for the time zone. * * <tr><td valign="top"><tt>'s'</tt> * <td valign="top"> <tt>'\u0073'</tt> * <td> Seconds since the beginning of the epoch starting at 1 January 1970 * <tt>00:00:00</tt> UTC, i.e. <tt>Long.MIN_VALUE/1000</tt> to * <tt>Long.MAX_VALUE/1000</tt>. * * <tr><td valign="top"><tt>'Q'</tt> * <td valign="top"> <tt>'\u004f'</tt> * <td> Milliseconds since the beginning of the epoch starting at 1 January * 1970 <tt>00:00:00</tt> UTC, i.e. <tt>Long.MIN_VALUE</tt> to * <tt>Long.MAX_VALUE</tt>. The precision of this value is limited by * the resolution of the underlying operating system or hardware. * * </table> * * <p> The following conversion characters are used for formatting dates: * * <table cellpadding=5 summary="date"> * * <tr><td valign="top"><tt>'B'</tt> * <td valign="top"> <tt>'\u0042'</tt> * <td> Locale-specific {@linkplain java.text.DateFormatSymbols#getMonths * full month name}, e.g. <tt>"January"</tt>, <tt>"February"</tt>. * * <tr><td valign="top"><tt>'b'</tt> * <td valign="top"> <tt>'\u0062'</tt> * <td> Locale-specific {@linkplain * java.text.DateFormatSymbols#getShortMonths abbreviated month name}, * e.g. <tt>"Jan"</tt>, <tt>"Feb"</tt>. * * <tr><td valign="top"><tt>'h'</tt> * <td valign="top"> <tt>'\u0068'</tt> * <td> Same as <tt>'b'</tt>. * * <tr><td valign="top"><tt>'A'</tt> * <td valign="top"> <tt>'\u0041'</tt> * <td> Locale-specific full name of the {@linkplain * java.text.DateFormatSymbols#getWeekdays day of the week}, * e.g. <tt>"Sunday"</tt>, <tt>"Monday"</tt> * * <tr><td valign="top"><tt>'a'</tt> * <td valign="top"> <tt>'\u0061'</tt> * <td> Locale-specific short name of the {@linkplain * java.text.DateFormatSymbols#getShortWeekdays day of the week}, * e.g. <tt>"Sun"</tt>, <tt>"Mon"</tt> * * <tr><td valign="top"><tt>'C'</tt> * <td valign="top"> <tt>'\u0043'</tt> * <td> Four-digit year divided by <tt>100</tt>, formatted as two digits * with leading zero as necessary, i.e. <tt>00 - 99</tt> * * <tr><td valign="top"><tt>'Y'</tt> * <td valign="top"> <tt>'\u0059'</tt> <td> Year, formatted to at least * four digits with leading zeros as necessary, e.g. <tt>0092</tt> equals * <tt>92</tt> CE for the Gregorian calendar. * * <tr><td valign="top"><tt>'y'</tt> * <td valign="top"> <tt>'\u0079'</tt> * <td> Last two digits of the year, formatted with leading zeros as * necessary, i.e. <tt>00 - 99</tt>. * * <tr><td valign="top"><tt>'j'</tt> * <td valign="top"> <tt>'\u006a'</tt> * <td> Day of year, formatted as three digits with leading zeros as * necessary, e.g. <tt>001 - 366</tt> for the Gregorian calendar. * <tt>001</tt> corresponds to the first day of the year. * * <tr><td valign="top"><tt>'m'</tt> * <td valign="top"> <tt>'\u006d'</tt> * <td> Month, formatted as two digits with leading zeros as necessary, * i.e. <tt>01 - 13</tt>, where "<tt>01</tt>" is the first month of the * year and ("<tt>13</tt>" is a special value required to support lunar * calendars). * * <tr><td valign="top"><tt>'d'</tt> * <td valign="top"> <tt>'\u0064'</tt> * <td> Day of month, formatted as two digits with leading zeros as * necessary, i.e. <tt>01 - 31</tt>, where "<tt>01</tt>" is the first day * of the month. * * <tr><td valign="top"><tt>'e'</tt> * <td valign="top"> <tt>'\u0065'</tt> * <td> Day of month, formatted as two digits, i.e. <tt>1 - 31</tt> where * "<tt>1</tt>" is the first day of the month. * * </table> * * <p> The following conversion characters are used for formatting common * date/time compositions. * * <table cellpadding=5 summary="composites"> * * <tr><td valign="top"><tt>'R'</tt> * <td valign="top"> <tt>'\u0052'</tt> * <td> Time formatted for the 24-hour clock as <tt>"%tH:%tM"</tt> * * <tr><td valign="top"><tt>'T'</tt> * <td valign="top"> <tt>'\u0054'</tt> * <td> Time formatted for the 24-hour clock as <tt>"%tH:%tM:%tS"</tt>. * * <tr><td valign="top"><tt>'r'</tt> * <td valign="top"> <tt>'\u0072'</tt> * <td> Time formatted for the 12-hour clock as <tt>"%tI:%tM:%tS * %Tp"</tt>. The location of the morning or afternoon marker * (<tt>'%Tp'</tt>) may be locale-dependent. * * <tr><td valign="top"><tt>'D'</tt> * <td valign="top"> <tt>'\u0044'</tt> * <td> Date formatted as <tt>"%tm/%td/%ty"</tt>. * * <tr><td valign="top"><tt>'F'</tt> * <td valign="top"> <tt>'\u0046'</tt> * <td> <a href="http://www.w3.org/TR/NOTE-datetime">ISO 8601</a> * complete date formatted as <tt>"%tY-%tm-%td"</tt>. * * <tr><td valign="top"><tt>'c'</tt> * <td valign="top"> <tt>'\u0063'</tt> * <td> Date and time formatted as <tt>"%ta %tb %td %tT %tZ %tY"</tt>, * e.g. <tt>"Sun Jul 20 16:17:00 EDT 1969"</tt>. * * </table> * * <p> The <tt>'-'</tt> flag defined for <a href="#dFlags">General * conversions</a> applies. If the <tt>'#'</tt> flag is given, then a {@link * FormatFlagsConversionMismatchException} will be thrown. * * <p> The <a name="dtWidth">width</a> is the minimum number of characters to * be written to the output. If the length of the converted value is less than * the <tt>width</tt> then the output will be padded by spaces * (<tt>'\u0020'</tt>) until the total number of characters equals width. * The padding is on the left by default. If the <tt>'-'</tt> flag is given * then the padding will be on the right. If width is not specified then there * is no minimum. * * <p> The precision is not applicable. If the precision is specified then an * {@link IllegalFormatPrecisionException} will be thrown. * * <h4><a name="dper">Percent</a></h4> * * <p> The conversion does not correspond to any argument. * * <table cellpadding=5 summary="DTConv"> * * <tr><td valign="top"><tt>'%'</tt> * <td> The result is a literal <tt>'%'</tt> (<tt>'\u0025'</tt>) * * <p> The <a name="dtWidth">width</a> is the minimum number of characters to * be written to the output including the <tt>'%'</tt>. If the length of the * converted value is less than the <tt>width</tt> then the output will be * padded by spaces (<tt>'\u0020'</tt>) until the total number of * characters equals width. The padding is on the left. If width is not * specified then just the <tt>'%'</tt> is output. * * <p> The <tt>'-'</tt> flag defined for <a href="#dFlags">General * conversions</a> applies. If any other flags are provided, then a * {@link FormatFlagsConversionMismatchException} will be thrown. * * <p> The precision is not applicable. If the precision is specified an * {@link IllegalFormatPrecisionException} will be thrown. * * </table> * * <h4><a name="dls">Line Separator</a></h4> * * <p> The conversion does not correspond to any argument. * * <table cellpadding=5 summary="DTConv"> * * <tr><td valign="top"><tt>'n'</tt> * <td> the platform-specific line separator as returned by {@link * System#getProperty System.getProperty("line.separator")}. * * </table> * * <p> Flags, width, and precision are not applicable. If any are provided an * {@link IllegalFormatFlagsException}, {@link IllegalFormatWidthException}, * and {@link IllegalFormatPrecisionException}, respectively will be thrown. * * <h4><a name="dpos">Argument Index</a></h4> * * <p> Format specifiers can reference arguments in three ways: * * <ul> * * <li> <i>Explicit indexing</i> is used when the format specifier contains an * argument index. The argument index is a decimal integer indicating the * position of the argument in the argument list. The first argument is * referenced by "<tt>1$</tt>", the second by "<tt>2$</tt>", etc. An argument * may be referenced more than once. * * <p> For example: * * <blockquote><pre> * formatter.format("%4$s %3$s %2$s %1$s %4$s %3$s %2$s %1$s", * "a", "b", "c", "d") * // -> "d c b a d c b a" * </pre></blockquote> * * <li> <i>Relative indexing</i> is used when the format specifier contains a * <tt>'<'</tt> (<tt>'\u003c'</tt>) flag which causes the argument for * the previous format specifier to be re-used. If there is no previous * argument, then a {@link MissingFormatArgumentException} is thrown. * * <blockquote><pre> * formatter.format("%s %s %<s %<s", "a", "b", "c", "d") * // -> "a b b b" * // "c" and "d" are ignored because they are not referenced * </pre></blockquote> * * <li> <i>Ordinary indexing</i> is used when the format specifier contains * neither an argument index nor a <tt>'<'</tt> flag. Each format specifier * which uses ordinary indexing is assigned a sequential implicit index into * argument list which is independent of the indices used by explicit or * relative indexing. * * <blockquote><pre> * formatter.format("%s %s %s %s", "a", "b", "c", "d") * // -> "a b c d" * </pre></blockquote> * * </ul> * * <p> It is possible to have a format string which uses all forms of indexing, * for example: * * <blockquote><pre> * formatter.format("%2$s %s %<s %s", "a", "b", "c", "d") * // -> "b a a b" * // "c" and "d" are ignored because they are not referenced * </pre></blockquote> * * <p> The maximum number of arguments is limited by the maximum dimension of a * Java array as defined by the <a * href="http://java.sun.com/docs/books/vmspec/">Java Virtual Machine * Specification</a>. If the argument index is does not correspond to an * available argument, then a {@link MissingFormatArgumentException} is thrown. * * <p> If there are more arguments than format specifiers, the extra arguments * are ignored. * * <p> Unless otherwise specified, passing a <tt>null</tt> argument to any * method or constructor in this class will cause a {@link * NullPointerException} to be thrown. * {@description.close} * * @author Iris Clark * @since 1.5 */ public final class Formatter implements Closeable, Flushable { private Appendable a; private Locale l; private IOException lastException; private char zero = '0'; private static double scaleUp; // 1 (sign) + 19 (max # sig digits) + 1 ('.') + 1 ('e') + 1 (sign) // + 3 (max # exp digits) + 4 (error) = 30 private static final int MAX_FD_CHARS = 30; // Initialize internal data. private void init(Appendable a, Locale l) { this.a = a; this.l = l; setZero(); } /** {@collect.stats} * {@description.open} * Constructs a new formatter. * * <p> The destination of the formatted output is a {@link StringBuilder} * which may be retrieved by invoking {@link #out out()} and whose * current content may be converted into a string by invoking {@link * #toString toString()}. The locale used is the {@linkplain * Locale#getDefault() default locale} for this instance of the Java * virtual machine. * {@description.close} */ public Formatter() { init(new StringBuilder(), Locale.getDefault()); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified destination. * * <p> The locale used is the {@linkplain Locale#getDefault() default * locale} for this instance of the Java virtual machine. * {@description.close} * * @param a * Destination for the formatted output. If <tt>a</tt> is * <tt>null</tt> then a {@link StringBuilder} will be created. */ public Formatter(Appendable a) { if (a == null) a = new StringBuilder(); init(a, Locale.getDefault()); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified locale. * * <p> The destination of the formatted output is a {@link StringBuilder} * which may be retrieved by invoking {@link #out out()} and whose current * content may be converted into a string by invoking {@link #toString * toString()}. * {@description.close} * * @param l * The {@linkplain java.util.Locale locale} to apply during * formatting. If <tt>l</tt> is <tt>null</tt> then no localization * is applied. */ public Formatter(Locale l) { init(new StringBuilder(), l); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified destination and locale. * {@description.close} * * @param a * Destination for the formatted output. If <tt>a</tt> is * <tt>null</tt> then a {@link StringBuilder} will be created. * * @param l * The {@linkplain java.util.Locale locale} to apply during * formatting. If <tt>l</tt> is <tt>null</tt> then no localization * is applied. */ public Formatter(Appendable a, Locale l) { if (a == null) a = new StringBuilder(); init(a, l); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified file name. * * <p> The charset used is the {@linkplain * java.nio.charset.Charset#defaultCharset() default charset} for this * instance of the Java virtual machine. * * <p> The locale used is the {@linkplain Locale#getDefault() default * locale} for this instance of the Java virtual machine. * {@description.close} * * @param fileName * The name of the file to use as the destination of this * formatter. If the file exists then it will be truncated to * zero size; otherwise, a new file will be created. The output * will be written to the file and is buffered. * * @throws SecurityException * If a security manager is present and {@link * SecurityManager#checkWrite checkWrite(fileName)} denies write * access to the file * * @throws FileNotFoundException * If the given file name does not denote an existing, writable * regular file and a new regular file of that name cannot be * created, or if some other error occurs while opening or * creating the file */ public Formatter(String fileName) throws FileNotFoundException { init(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileName))), Locale.getDefault()); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified file name and charset. * * <p> The locale used is the {@linkplain Locale#getDefault default * locale} for this instance of the Java virtual machine. * {@description.close} * * @param fileName * The name of the file to use as the destination of this * formatter. If the file exists then it will be truncated to * zero size; otherwise, a new file will be created. The output * will be written to the file and is buffered. * * @param csn * The name of a supported {@linkplain java.nio.charset.Charset * charset} * * @throws FileNotFoundException * If the given file name does not denote an existing, writable * regular file and a new regular file of that name cannot be * created, or if some other error occurs while opening or * creating the file * * @throws SecurityException * If a security manager is present and {@link * SecurityManager#checkWrite checkWrite(fileName)} denies write * access to the file * * @throws UnsupportedEncodingException * If the named charset is not supported */ public Formatter(String fileName, String csn) throws FileNotFoundException, UnsupportedEncodingException { this(fileName, csn, Locale.getDefault()); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified file name, charset, and * locale. * {@description.close} * * @param fileName * The name of the file to use as the destination of this * formatter. If the file exists then it will be truncated to * zero size; otherwise, a new file will be created. The output * will be written to the file and is buffered. * * @param csn * The name of a supported {@linkplain java.nio.charset.Charset * charset} * * @param l * The {@linkplain java.util.Locale locale} to apply during * formatting. If <tt>l</tt> is <tt>null</tt> then no localization * is applied. * * @throws FileNotFoundException * If the given file name does not denote an existing, writable * regular file and a new regular file of that name cannot be * created, or if some other error occurs while opening or * creating the file * * @throws SecurityException * If a security manager is present and {@link * SecurityManager#checkWrite checkWrite(fileName)} denies write * access to the file * * @throws UnsupportedEncodingException * If the named charset is not supported */ public Formatter(String fileName, String csn, Locale l) throws FileNotFoundException, UnsupportedEncodingException { init(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileName), csn)), l); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified file. * * <p> The charset used is the {@linkplain * java.nio.charset.Charset#defaultCharset() default charset} for this * instance of the Java virtual machine. * * <p> The locale used is the {@linkplain Locale#getDefault() default * locale} for this instance of the Java virtual machine. * {@description.close} * * @param file * The file to use as the destination of this formatter. If the * file exists then it will be truncated to zero size; otherwise, * a new file will be created. The output will be written to the * file and is buffered. * * @throws SecurityException * If a security manager is present and {@link * SecurityManager#checkWrite checkWrite(file.getPath())} denies * write access to the file * * @throws FileNotFoundException * If the given file object does not denote an existing, writable * regular file and a new regular file of that name cannot be * created, or if some other error occurs while opening or * creating the file */ public Formatter(File file) throws FileNotFoundException { init(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file))), Locale.getDefault()); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified file and charset. * * <p> The locale used is the {@linkplain Locale#getDefault default * locale} for this instance of the Java virtual machine. * {@description.close} * * @param file * The file to use as the destination of this formatter. If the * file exists then it will be truncated to zero size; otherwise, * a new file will be created. The output will be written to the * file and is buffered. * * @param csn * The name of a supported {@linkplain java.nio.charset.Charset * charset} * * @throws FileNotFoundException * If the given file object does not denote an existing, writable * regular file and a new regular file of that name cannot be * created, or if some other error occurs while opening or * creating the file * * @throws SecurityException * If a security manager is present and {@link * SecurityManager#checkWrite checkWrite(file.getPath())} denies * write access to the file * * @throws UnsupportedEncodingException * If the named charset is not supported */ public Formatter(File file, String csn) throws FileNotFoundException, UnsupportedEncodingException { this(file, csn, Locale.getDefault()); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified file, charset, and * locale. * {@description.close} * * @param file * The file to use as the destination of this formatter. If the * file exists then it will be truncated to zero size; otherwise, * a new file will be created. The output will be written to the * file and is buffered. * * @param csn * The name of a supported {@linkplain java.nio.charset.Charset * charset} * * @param l * The {@linkplain java.util.Locale locale} to apply during * formatting. If <tt>l</tt> is <tt>null</tt> then no localization * is applied. * * @throws FileNotFoundException * If the given file object does not denote an existing, writable * regular file and a new regular file of that name cannot be * created, or if some other error occurs while opening or * creating the file * * @throws SecurityException * If a security manager is present and {@link * SecurityManager#checkWrite checkWrite(file.getPath())} denies * write access to the file * * @throws UnsupportedEncodingException * If the named charset is not supported */ public Formatter(File file, String csn, Locale l) throws FileNotFoundException, UnsupportedEncodingException { init(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), csn)), l); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified print stream. * * <p> The locale used is the {@linkplain Locale#getDefault() default * locale} for this instance of the Java virtual machine. * * <p> Characters are written to the given {@link java.io.PrintStream * PrintStream} object and are therefore encoded using that object's * charset. * {@description.close} * * @param ps * The stream to use as the destination of this formatter. */ public Formatter(PrintStream ps) { if (ps == null) throw new NullPointerException(); init((Appendable)ps, Locale.getDefault()); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified output stream. * * <p> The charset used is the {@linkplain * java.nio.charset.Charset#defaultCharset() default charset} for this * instance of the Java virtual machine. * * <p> The locale used is the {@linkplain Locale#getDefault() default * locale} for this instance of the Java virtual machine. * {@description.close} * * @param os * The output stream to use as the destination of this formatter. * The output will be buffered. */ public Formatter(OutputStream os) { init(new BufferedWriter(new OutputStreamWriter(os)), Locale.getDefault()); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified output stream and * charset. * * <p> The locale used is the {@linkplain Locale#getDefault default * locale} for this instance of the Java virtual machine. * {@description.close} * * @param os * The output stream to use as the destination of this formatter. * The output will be buffered. * * @param csn * The name of a supported {@linkplain java.nio.charset.Charset * charset} * * @throws UnsupportedEncodingException * If the named charset is not supported */ public Formatter(OutputStream os, String csn) throws UnsupportedEncodingException { this(os, csn, Locale.getDefault()); } /** {@collect.stats} * {@description.open} * Constructs a new formatter with the specified output stream, charset, * and locale. * {@description.close} * * @param os * The output stream to use as the destination of this formatter. * The output will be buffered. * * @param csn * The name of a supported {@linkplain java.nio.charset.Charset * charset} * * @param l * The {@linkplain java.util.Locale locale} to apply during * formatting. If <tt>l</tt> is <tt>null</tt> then no localization * is applied. * * @throws UnsupportedEncodingException * If the named charset is not supported */ public Formatter(OutputStream os, String csn, Locale l) throws UnsupportedEncodingException { init(new BufferedWriter(new OutputStreamWriter(os, csn)), l); } private void setZero() { if ((l != null) && !l.equals(Locale.US)) { DecimalFormatSymbols dfs = DecimalFormatSymbols.getInstance(l); zero = dfs.getZeroDigit(); } } /** {@collect.stats} * {@description.open} * Returns the locale set by the construction of this formatter. * * <p> The {@link #format(java.util.Locale,String,Object...) format} method * for this object which has a locale argument does not change this value. * {@description.close} * * @return <tt>null</tt> if no localization is applied, otherwise a * locale * * @throws FormatterClosedException * If this formatter has been closed by invoking its {@link * #close()} method */ public Locale locale() { ensureOpen(); return l; } /** {@collect.stats} * {@description.open} * Returns the destination for the output. * {@description.close} * * @return The destination for the output * * @throws FormatterClosedException * If this formatter has been closed by invoking its {@link * #close()} method */ public Appendable out() { ensureOpen(); return a; } /** {@collect.stats} * {@description.open} * Returns the result of invoking <tt>toString()</tt> on the destination * for the output. For example, the following code formats text into a * {@link StringBuilder} then retrieves the resultant string: * * <blockquote><pre> * Formatter f = new Formatter(); * f.format("Last reboot at %tc", lastRebootDate); * String s = f.toString(); * // -> s == "Last reboot at Sat Jan 01 00:00:00 PST 2000" * </pre></blockquote> * * <p> An invocation of this method behaves in exactly the same way as the * invocation * * <pre> * out().toString() </pre> * * <p> Depending on the specification of <tt>toString</tt> for the {@link * Appendable}, the returned string may or may not contain the characters * written to the destination. For instance, buffers typically return * their contents in <tt>toString()</tt>, but streams cannot since the * data is discarded. * {@description.close} * * @return The result of invoking <tt>toString()</tt> on the destination * for the output * * @throws FormatterClosedException * If this formatter has been closed by invoking its {@link * #close()} method */ public String toString() { ensureOpen(); return a.toString(); } /** {@collect.stats} * {@description.open} * Flushes this formatter. If the destination implements the {@link * java.io.Flushable} interface, its <tt>flush</tt> method will be invoked. * * <p> Flushing a formatter writes any buffered output in the destination * to the underlying stream. * {@description.close} * * @throws FormatterClosedException * If this formatter has been closed by invoking its {@link * #close()} method */ public void flush() { ensureOpen(); if (a instanceof Flushable) { try { ((Flushable)a).flush(); } catch (IOException ioe) { lastException = ioe; } } } /** {@collect.stats} * {@description.open} * Closes this formatter. If the destination implements the {@link * java.io.Closeable} interface, its <tt>close</tt> method will be invoked. * * <p> Closing a formatter allows it to release resources it may be holding * (such as open files). If the formatter is already closed, then invoking * this method has no effect. * * <p> Attempting to invoke any methods except {@link #ioException()} in * this formatter after it has been closed will result in a {@link * FormatterClosedException}. * {@description.close} */ public void close() { if (a == null) return; try { if (a instanceof Closeable) ((Closeable)a).close(); } catch (IOException ioe) { lastException = ioe; } finally { a = null; } } private void ensureOpen() { if (a == null) throw new FormatterClosedException(); } /** {@collect.stats} * {@description.open} * Returns the <tt>IOException</tt> last thrown by this formatter's {@link * Appendable}. * * <p> If the destination's <tt>append()</tt> method never throws * <tt>IOException</tt>, then this method will always return <tt>null</tt>. * {@description.close} * * @return The last exception thrown by the Appendable or <tt>null</tt> if * no such exception exists. */ public IOException ioException() { return lastException; } /** {@collect.stats} * {@description.open} * Writes a formatted string to this object's destination using the * specified format string and arguments. The locale used is the one * defined during the construction of this formatter. * {@description.close} * * @param format * A format string as described in <a href="#syntax">Format string * syntax</a>. * * @param args * Arguments referenced by the format specifiers in the format * string. If there are more arguments than format specifiers, the * extra arguments are ignored. The maximum number of arguments is * limited by the maximum dimension of a Java array as defined by * the <a href="http://java.sun.com/docs/books/vmspec/">Java * Virtual Machine Specification</a>. * * @throws IllegalFormatException * If a format string contains an illegal syntax, a format * specifier that is incompatible with the given arguments, * insufficient arguments given the format string, or other * illegal conditions. For specification of all possible * formatting errors, see the <a href="#detail">Details</a> * section of the formatter class specification. * * @throws FormatterClosedException * If this formatter has been closed by invoking its {@link * #close()} method * * @return This formatter */ public Formatter format(String format, Object ... args) { return format(l, format, args); } /** {@collect.stats} * {@description.open} * Writes a formatted string to this object's destination using the * specified locale, format string, and arguments. * {@description.close} * * @param l * The {@linkplain java.util.Locale locale} to apply during * formatting. If <tt>l</tt> is <tt>null</tt> then no localization * is applied. This does not change this object's locale that was * set during construction. * * @param format * A format string as described in <a href="#syntax">Format string * syntax</a> * * @param args * Arguments referenced by the format specifiers in the format * string. If there are more arguments than format specifiers, the * extra arguments are ignored. The maximum number of arguments is * limited by the maximum dimension of a Java array as defined by * the <a href="http://java.sun.com/docs/books/vmspec/">Java * Virtual Machine Specification</a> * * @throws IllegalFormatException * If a format string contains an illegal syntax, a format * specifier that is incompatible with the given arguments, * insufficient arguments given the format string, or other * illegal conditions. For specification of all possible * formatting errors, see the <a href="#detail">Details</a> * section of the formatter class specification. * * @throws FormatterClosedException * If this formatter has been closed by invoking its {@link * #close()} method * * @return This formatter */ public Formatter format(Locale l, String format, Object ... args) { ensureOpen(); // index of last argument referenced int last = -1; // last ordinary index int lasto = -1; FormatString[] fsa = parse(format); for (int i = 0; i < fsa.length; i++) { FormatString fs = fsa[i]; int index = fs.index(); try { switch (index) { case -2: // fixed string, "%n", or "%%" fs.print(null, l); break; case -1: // relative index if (last < 0 || (args != null && last > args.length - 1)) throw new MissingFormatArgumentException(fs.toString()); fs.print((args == null ? null : args[last]), l); break; case 0: // ordinary index lasto++; last = lasto; if (args != null && lasto > args.length - 1) throw new MissingFormatArgumentException(fs.toString()); fs.print((args == null ? null : args[lasto]), l); break; default: // explicit index last = index - 1; if (args != null && last > args.length - 1) throw new MissingFormatArgumentException(fs.toString()); fs.print((args == null ? null : args[last]), l); break; } } catch (IOException x) { lastException = x; } } return this; } // %[argument_index$][flags][width][.precision][t]conversion private static final String formatSpecifier = "%(\\d+\\$)?([-#+ 0,(\\<]*)?(\\d+)?(\\.\\d+)?([tT])?([a-zA-Z%])"; private static Pattern fsPattern = Pattern.compile(formatSpecifier); // Look for format specifiers in the format string. private FormatString[] parse(String s) { ArrayList al = new ArrayList(); Matcher m = fsPattern.matcher(s); int i = 0; while (i < s.length()) { if (m.find(i)) { // Anything between the start of the string and the beginning // of the format specifier is either fixed text or contains // an invalid format string. if (m.start() != i) { // Make sure we didn't miss any invalid format specifiers checkText(s.substring(i, m.start())); // Assume previous characters were fixed text al.add(new FixedString(s.substring(i, m.start()))); } // Expect 6 groups in regular expression String[] sa = new String[6]; for (int j = 0; j < m.groupCount(); j++) { sa[j] = m.group(j + 1); // System.out.print(sa[j] + " "); } // System.out.println(); al.add(new FormatSpecifier(this, sa)); i = m.end(); } else { // No more valid format specifiers. Check for possible invalid // format specifiers. checkText(s.substring(i)); // The rest of the string is fixed text al.add(new FixedString(s.substring(i))); break; } } // FormatString[] fs = new FormatString[al.size()]; // for (int j = 0; j < al.size(); j++) // System.out.println(((FormatString) al.get(j)).toString()); return (FormatString[]) al.toArray(new FormatString[0]); } private void checkText(String s) { int idx; // If there are any '%' in the given string, we got a bad format // specifier. if ((idx = s.indexOf('%')) != -1) { char c = (idx > s.length() - 2 ? '%' : s.charAt(idx + 1)); throw new UnknownFormatConversionException(String.valueOf(c)); } } private interface FormatString { int index(); void print(Object arg, Locale l) throws IOException; String toString(); } private class FixedString implements FormatString { private String s; FixedString(String s) { this.s = s; } public int index() { return -2; } public void print(Object arg, Locale l) throws IOException { a.append(s); } public String toString() { return s; } } public enum BigDecimalLayoutForm { SCIENTIFIC, DECIMAL_FLOAT }; private class FormatSpecifier implements FormatString { private int index = -1; private Flags f = Flags.NONE; private int width; private int precision; private boolean dt = false; private char c; private Formatter formatter; // cache the line separator private String ls; private int index(String s) { if (s != null) { try { index = Integer.parseInt(s.substring(0, s.length() - 1)); } catch (NumberFormatException x) { assert(false); } } else { index = 0; } return index; } public int index() { return index; } private Flags flags(String s) { f = Flags.parse(s); if (f.contains(Flags.PREVIOUS)) index = -1; return f; } Flags flags() { return f; } private int width(String s) { width = -1; if (s != null) { try { width = Integer.parseInt(s); if (width < 0) throw new IllegalFormatWidthException(width); } catch (NumberFormatException x) { assert(false); } } return width; } int width() { return width; } private int precision(String s) { precision = -1; if (s != null) { try { // remove the '.' precision = Integer.parseInt(s.substring(1)); if (precision < 0) throw new IllegalFormatPrecisionException(precision); } catch (NumberFormatException x) { assert(false); } } return precision; } int precision() { return precision; } private char conversion(String s) { c = s.charAt(0); if (!dt) { if (!Conversion.isValid(c)) throw new UnknownFormatConversionException(String.valueOf(c)); if (Character.isUpperCase(c)) f.add(Flags.UPPERCASE); c = Character.toLowerCase(c); if (Conversion.isText(c)) index = -2; } return c; } private char conversion() { return c; } FormatSpecifier(Formatter formatter, String[] sa) { this.formatter = formatter; int idx = 0; index(sa[idx++]); flags(sa[idx++]); width(sa[idx++]); precision(sa[idx++]); if (sa[idx] != null) { dt = true; if (sa[idx].equals("T")) f.add(Flags.UPPERCASE); } conversion(sa[++idx]); if (dt) checkDateTime(); else if (Conversion.isGeneral(c)) checkGeneral(); else if (Conversion.isCharacter(c)) checkCharacter(); else if (Conversion.isInteger(c)) checkInteger(); else if (Conversion.isFloat(c)) checkFloat(); else if (Conversion.isText(c)) checkText(); else throw new UnknownFormatConversionException(String.valueOf(c)); } public void print(Object arg, Locale l) throws IOException { if (dt) { printDateTime(arg, l); return; } switch(c) { case Conversion.DECIMAL_INTEGER: case Conversion.OCTAL_INTEGER: case Conversion.HEXADECIMAL_INTEGER: printInteger(arg, l); break; case Conversion.SCIENTIFIC: case Conversion.GENERAL: case Conversion.DECIMAL_FLOAT: case Conversion.HEXADECIMAL_FLOAT: printFloat(arg, l); break; case Conversion.CHARACTER: case Conversion.CHARACTER_UPPER: printCharacter(arg); break; case Conversion.BOOLEAN: printBoolean(arg); break; case Conversion.STRING: printString(arg, l); break; case Conversion.HASHCODE: printHashCode(arg); break; case Conversion.LINE_SEPARATOR: if (ls == null) ls = System.getProperty("line.separator"); a.append(ls); break; case Conversion.PERCENT_SIGN: a.append('%'); break; default: assert false; } } private void printInteger(Object arg, Locale l) throws IOException { if (arg == null) print("null"); else if (arg instanceof Byte) print(((Byte)arg).byteValue(), l); else if (arg instanceof Short) print(((Short)arg).shortValue(), l); else if (arg instanceof Integer) print(((Integer)arg).intValue(), l); else if (arg instanceof Long) print(((Long)arg).longValue(), l); else if (arg instanceof BigInteger) print(((BigInteger)arg), l); else failConversion(c, arg); } private void printFloat(Object arg, Locale l) throws IOException { if (arg == null) print("null"); else if (arg instanceof Float) print(((Float)arg).floatValue(), l); else if (arg instanceof Double) print(((Double)arg).doubleValue(), l); else if (arg instanceof BigDecimal) print(((BigDecimal)arg), l); else failConversion(c, arg); } private void printDateTime(Object arg, Locale l) throws IOException { if (arg == null) { print("null"); return; } Calendar cal = null; // Instead of Calendar.setLenient(true), perhaps we should // wrap the IllegalArgumentException that might be thrown? if (arg instanceof Long) { // Note that the following method uses an instance of the // default time zone (TimeZone.getDefaultRef(). cal = Calendar.getInstance(l == null ? Locale.US : l); cal.setTimeInMillis((Long)arg); } else if (arg instanceof Date) { // Note that the following method uses an instance of the // default time zone (TimeZone.getDefaultRef(). cal = Calendar.getInstance(l == null ? Locale.US : l); cal.setTime((Date)arg); } else if (arg instanceof Calendar) { cal = (Calendar) ((Calendar)arg).clone(); cal.setLenient(true); } else { failConversion(c, arg); } // Use the provided locale so that invocations of // localizedMagnitude() use optimizations for null. print(cal, c, l); } private void printCharacter(Object arg) throws IOException { if (arg == null) { print("null"); return; } String s = null; if (arg instanceof Character) { s = ((Character)arg).toString(); } else if (arg instanceof Byte) { byte i = ((Byte)arg).byteValue(); if (Character.isValidCodePoint(i)) s = new String(Character.toChars(i)); else throw new IllegalFormatCodePointException(i); } else if (arg instanceof Short) { short i = ((Short)arg).shortValue(); if (Character.isValidCodePoint(i)) s = new String(Character.toChars(i)); else throw new IllegalFormatCodePointException(i); } else if (arg instanceof Integer) { int i = ((Integer)arg).intValue(); if (Character.isValidCodePoint(i)) s = new String(Character.toChars(i)); else throw new IllegalFormatCodePointException(i); } else { failConversion(c, arg); } print(s); } private void printString(Object arg, Locale l) throws IOException { if (arg == null) { print("null"); } else if (arg instanceof Formattable) { Formatter fmt = formatter; if (formatter.locale() != l) fmt = new Formatter(formatter.out(), l); ((Formattable)arg).formatTo(fmt, f.valueOf(), width, precision); } else { print(arg.toString()); } } private void printBoolean(Object arg) throws IOException { String s; if (arg != null) s = ((arg instanceof Boolean) ? ((Boolean)arg).toString() : Boolean.toString(true)); else s = Boolean.toString(false); print(s); } private void printHashCode(Object arg) throws IOException { String s = (arg == null ? "null" : Integer.toHexString(arg.hashCode())); print(s); } private void print(String s) throws IOException { if (precision != -1 && precision < s.length()) s = s.substring(0, precision); if (f.contains(Flags.UPPERCASE)) s = s.toUpperCase(); a.append(justify(s)); } private String justify(String s) { if (width == -1) return s; StringBuilder sb = new StringBuilder(); boolean pad = f.contains(Flags.LEFT_JUSTIFY); int sp = width - s.length(); if (!pad) for (int i = 0; i < sp; i++) sb.append(' '); sb.append(s); if (pad) for (int i = 0; i < sp; i++) sb.append(' '); return sb.toString(); } public String toString() { StringBuilder sb = new StringBuilder('%'); // Flags.UPPERCASE is set internally for legal conversions. Flags dupf = f.dup().remove(Flags.UPPERCASE); sb.append(dupf.toString()); if (index > 0) sb.append(index).append('$'); if (width != -1) sb.append(width); if (precision != -1) sb.append('.').append(precision); if (dt) sb.append(f.contains(Flags.UPPERCASE) ? 'T' : 't'); sb.append(f.contains(Flags.UPPERCASE) ? Character.toUpperCase(c) : c); return sb.toString(); } private void checkGeneral() { if ((c == Conversion.BOOLEAN || c == Conversion.HASHCODE) && f.contains(Flags.ALTERNATE)) failMismatch(Flags.ALTERNATE, c); // '-' requires a width if (width == -1 && f.contains(Flags.LEFT_JUSTIFY)) throw new MissingFormatWidthException(toString()); checkBadFlags(Flags.PLUS, Flags.LEADING_SPACE, Flags.ZERO_PAD, Flags.GROUP, Flags.PARENTHESES); } private void checkDateTime() { if (precision != -1) throw new IllegalFormatPrecisionException(precision); if (!DateTime.isValid(c)) throw new UnknownFormatConversionException("t" + c); checkBadFlags(Flags.ALTERNATE, Flags.PLUS, Flags.LEADING_SPACE, Flags.ZERO_PAD, Flags.GROUP, Flags.PARENTHESES); // '-' requires a width if (width == -1 && f.contains(Flags.LEFT_JUSTIFY)) throw new MissingFormatWidthException(toString()); } private void checkCharacter() { if (precision != -1) throw new IllegalFormatPrecisionException(precision); checkBadFlags(Flags.ALTERNATE, Flags.PLUS, Flags.LEADING_SPACE, Flags.ZERO_PAD, Flags.GROUP, Flags.PARENTHESES); // '-' requires a width if (width == -1 && f.contains(Flags.LEFT_JUSTIFY)) throw new MissingFormatWidthException(toString()); } private void checkInteger() { checkNumeric(); if (precision != -1) throw new IllegalFormatPrecisionException(precision); if (c == Conversion.DECIMAL_INTEGER) checkBadFlags(Flags.ALTERNATE); else if (c == Conversion.OCTAL_INTEGER) checkBadFlags(Flags.GROUP); else checkBadFlags(Flags.GROUP); } private void checkBadFlags(Flags ... badFlags) { for (int i = 0; i < badFlags.length; i++) if (f.contains(badFlags[i])) failMismatch(badFlags[i], c); } private void checkFloat() { checkNumeric(); if (c == Conversion.DECIMAL_FLOAT) { } else if (c == Conversion.HEXADECIMAL_FLOAT) { checkBadFlags(Flags.PARENTHESES, Flags.GROUP); } else if (c == Conversion.SCIENTIFIC) { checkBadFlags(Flags.GROUP); } else if (c == Conversion.GENERAL) { checkBadFlags(Flags.ALTERNATE); } } private void checkNumeric() { if (width != -1 && width < 0) throw new IllegalFormatWidthException(width); if (precision != -1 && precision < 0) throw new IllegalFormatPrecisionException(precision); // '-' and '0' require a width if (width == -1 && (f.contains(Flags.LEFT_JUSTIFY) || f.contains(Flags.ZERO_PAD))) throw new MissingFormatWidthException(toString()); // bad combination if ((f.contains(Flags.PLUS) && f.contains(Flags.LEADING_SPACE)) || (f.contains(Flags.LEFT_JUSTIFY) && f.contains(Flags.ZERO_PAD))) throw new IllegalFormatFlagsException(f.toString()); } private void checkText() { if (precision != -1) throw new IllegalFormatPrecisionException(precision); switch (c) { case Conversion.PERCENT_SIGN: if (f.valueOf() != Flags.LEFT_JUSTIFY.valueOf() && f.valueOf() != Flags.NONE.valueOf()) throw new IllegalFormatFlagsException(f.toString()); // '-' requires a width if (width == -1 && f.contains(Flags.LEFT_JUSTIFY)) throw new MissingFormatWidthException(toString()); break; case Conversion.LINE_SEPARATOR: if (width != -1) throw new IllegalFormatWidthException(width); if (f.valueOf() != Flags.NONE.valueOf()) throw new IllegalFormatFlagsException(f.toString()); break; default: assert false; } } private void print(byte value, Locale l) throws IOException { long v = value; if (value < 0 && (c == Conversion.OCTAL_INTEGER || c == Conversion.HEXADECIMAL_INTEGER)) { v += (1L << 8); assert v >= 0 : v; } print(v, l); } private void print(short value, Locale l) throws IOException { long v = value; if (value < 0 && (c == Conversion.OCTAL_INTEGER || c == Conversion.HEXADECIMAL_INTEGER)) { v += (1L << 16); assert v >= 0 : v; } print(v, l); } private void print(int value, Locale l) throws IOException { long v = value; if (value < 0 && (c == Conversion.OCTAL_INTEGER || c == Conversion.HEXADECIMAL_INTEGER)) { v += (1L << 32); assert v >= 0 : v; } print(v, l); } private void print(long value, Locale l) throws IOException { StringBuilder sb = new StringBuilder(); if (c == Conversion.DECIMAL_INTEGER) { boolean neg = value < 0; char[] va; if (value < 0) va = Long.toString(value, 10).substring(1).toCharArray(); else va = Long.toString(value, 10).toCharArray(); // leading sign indicator leadingSign(sb, neg); // the value localizedMagnitude(sb, va, f, adjustWidth(width, f, neg), l); // trailing sign indicator trailingSign(sb, neg); } else if (c == Conversion.OCTAL_INTEGER) { checkBadFlags(Flags.PARENTHESES, Flags.LEADING_SPACE, Flags.PLUS); String s = Long.toOctalString(value); int len = (f.contains(Flags.ALTERNATE) ? s.length() + 1 : s.length()); // apply ALTERNATE (radix indicator for octal) before ZERO_PAD if (f.contains(Flags.ALTERNATE)) sb.append('0'); if (f.contains(Flags.ZERO_PAD)) for (int i = 0; i < width - len; i++) sb.append('0'); sb.append(s); } else if (c == Conversion.HEXADECIMAL_INTEGER) { checkBadFlags(Flags.PARENTHESES, Flags.LEADING_SPACE, Flags.PLUS); String s = Long.toHexString(value); int len = (f.contains(Flags.ALTERNATE) ? s.length() + 2 : s.length()); // apply ALTERNATE (radix indicator for hex) before ZERO_PAD if (f.contains(Flags.ALTERNATE)) sb.append(f.contains(Flags.UPPERCASE) ? "0X" : "0x"); if (f.contains(Flags.ZERO_PAD)) for (int i = 0; i < width - len; i++) sb.append('0'); if (f.contains(Flags.UPPERCASE)) s = s.toUpperCase(); sb.append(s); } // justify based on width a.append(justify(sb.toString())); } // neg := val < 0 private StringBuilder leadingSign(StringBuilder sb, boolean neg) { if (!neg) { if (f.contains(Flags.PLUS)) { sb.append('+'); } else if (f.contains(Flags.LEADING_SPACE)) { sb.append(' '); } } else { if (f.contains(Flags.PARENTHESES)) sb.append('('); else sb.append('-'); } return sb; } // neg := val < 0 private StringBuilder trailingSign(StringBuilder sb, boolean neg) { if (neg && f.contains(Flags.PARENTHESES)) sb.append(')'); return sb; } private void print(BigInteger value, Locale l) throws IOException { StringBuilder sb = new StringBuilder(); boolean neg = value.signum() == -1; BigInteger v = value.abs(); // leading sign indicator leadingSign(sb, neg); // the value if (c == Conversion.DECIMAL_INTEGER) { char[] va = v.toString().toCharArray(); localizedMagnitude(sb, va, f, adjustWidth(width, f, neg), l); } else if (c == Conversion.OCTAL_INTEGER) { String s = v.toString(8); int len = s.length() + sb.length(); if (neg && f.contains(Flags.PARENTHESES)) len++; // apply ALTERNATE (radix indicator for octal) before ZERO_PAD if (f.contains(Flags.ALTERNATE)) { len++; sb.append('0'); } if (f.contains(Flags.ZERO_PAD)) { for (int i = 0; i < width - len; i++) sb.append('0'); } sb.append(s); } else if (c == Conversion.HEXADECIMAL_INTEGER) { String s = v.toString(16); int len = s.length() + sb.length(); if (neg && f.contains(Flags.PARENTHESES)) len++; // apply ALTERNATE (radix indicator for hex) before ZERO_PAD if (f.contains(Flags.ALTERNATE)) { len += 2; sb.append(f.contains(Flags.UPPERCASE) ? "0X" : "0x"); } if (f.contains(Flags.ZERO_PAD)) for (int i = 0; i < width - len; i++) sb.append('0'); if (f.contains(Flags.UPPERCASE)) s = s.toUpperCase(); sb.append(s); } // trailing sign indicator trailingSign(sb, (value.signum() == -1)); // justify based on width a.append(justify(sb.toString())); } private void print(float value, Locale l) throws IOException { print((double) value, l); } private void print(double value, Locale l) throws IOException { StringBuilder sb = new StringBuilder(); boolean neg = Double.compare(value, 0.0) == -1; if (!Double.isNaN(value)) { double v = Math.abs(value); // leading sign indicator leadingSign(sb, neg); // the value if (!Double.isInfinite(v)) print(sb, v, l, f, c, precision, neg); else sb.append(f.contains(Flags.UPPERCASE) ? "INFINITY" : "Infinity"); // trailing sign indicator trailingSign(sb, neg); } else { sb.append(f.contains(Flags.UPPERCASE) ? "NAN" : "NaN"); } // justify based on width a.append(justify(sb.toString())); } // !Double.isInfinite(value) && !Double.isNaN(value) private void print(StringBuilder sb, double value, Locale l, Flags f, char c, int precision, boolean neg) throws IOException { if (c == Conversion.SCIENTIFIC) { // Create a new FormattedFloatingDecimal with the desired // precision. int prec = (precision == -1 ? 6 : precision); FormattedFloatingDecimal fd = new FormattedFloatingDecimal(value, prec, FormattedFloatingDecimal.Form.SCIENTIFIC); char[] v = new char[MAX_FD_CHARS]; int len = fd.getChars(v); char[] mant = addZeros(mantissa(v, len), prec); // If the precision is zero and the '#' flag is set, add the // requested decimal point. if (f.contains(Flags.ALTERNATE) && (prec == 0)) mant = addDot(mant); char[] exp = (value == 0.0) ? new char[] {'+','0','0'} : exponent(v, len); int newW = width; if (width != -1) newW = adjustWidth(width - exp.length - 1, f, neg); localizedMagnitude(sb, mant, f, newW, l); sb.append(f.contains(Flags.UPPERCASE) ? 'E' : 'e'); Flags flags = f.dup().remove(Flags.GROUP); char sign = exp[0]; assert(sign == '+' || sign == '-'); sb.append(sign); char[] tmp = new char[exp.length - 1]; System.arraycopy(exp, 1, tmp, 0, exp.length - 1); sb.append(localizedMagnitude(null, tmp, flags, -1, l)); } else if (c == Conversion.DECIMAL_FLOAT) { // Create a new FormattedFloatingDecimal with the desired // precision. int prec = (precision == -1 ? 6 : precision); FormattedFloatingDecimal fd = new FormattedFloatingDecimal(value, prec, FormattedFloatingDecimal.Form.DECIMAL_FLOAT); // MAX_FD_CHARS + 1 (round?) char[] v = new char[MAX_FD_CHARS + 1 + Math.abs(fd.getExponent())]; int len = fd.getChars(v); char[] mant = addZeros(mantissa(v, len), prec); // If the precision is zero and the '#' flag is set, add the // requested decimal point. if (f.contains(Flags.ALTERNATE) && (prec == 0)) mant = addDot(mant); int newW = width; if (width != -1) newW = adjustWidth(width, f, neg); localizedMagnitude(sb, mant, f, newW, l); } else if (c == Conversion.GENERAL) { int prec = precision; if (precision == -1) prec = 6; else if (precision == 0) prec = 1; FormattedFloatingDecimal fd = new FormattedFloatingDecimal(value, prec, FormattedFloatingDecimal.Form.GENERAL); // MAX_FD_CHARS + 1 (round?) char[] v = new char[MAX_FD_CHARS + 1 + Math.abs(fd.getExponent())]; int len = fd.getChars(v); char[] exp = exponent(v, len); if (exp != null) { prec -= 1; } else { prec = prec - (value == 0 ? 0 : fd.getExponentRounded()) - 1; } char[] mant = addZeros(mantissa(v, len), prec); // If the precision is zero and the '#' flag is set, add the // requested decimal point. if (f.contains(Flags.ALTERNATE) && (prec == 0)) mant = addDot(mant); int newW = width; if (width != -1) { if (exp != null) newW = adjustWidth(width - exp.length - 1, f, neg); else newW = adjustWidth(width, f, neg); } localizedMagnitude(sb, mant, f, newW, l); if (exp != null) { sb.append(f.contains(Flags.UPPERCASE) ? 'E' : 'e'); Flags flags = f.dup().remove(Flags.GROUP); char sign = exp[0]; assert(sign == '+' || sign == '-'); sb.append(sign); char[] tmp = new char[exp.length - 1]; System.arraycopy(exp, 1, tmp, 0, exp.length - 1); sb.append(localizedMagnitude(null, tmp, flags, -1, l)); } } else if (c == Conversion.HEXADECIMAL_FLOAT) { int prec = precision; if (precision == -1) // assume that we want all of the digits prec = 0; else if (precision == 0) prec = 1; String s = hexDouble(value, prec); char[] va; boolean upper = f.contains(Flags.UPPERCASE); sb.append(upper ? "0X" : "0x"); if (f.contains(Flags.ZERO_PAD)) for (int i = 0; i < width - s.length() - 2; i++) sb.append('0'); int idx = s.indexOf('p'); va = s.substring(0, idx).toCharArray(); if (upper) { String tmp = new String(va); // don't localize hex tmp = tmp.toUpperCase(Locale.US); va = tmp.toCharArray(); } sb.append(prec != 0 ? addZeros(va, prec) : va); sb.append(upper ? 'P' : 'p'); sb.append(s.substring(idx+1)); } } private char[] mantissa(char[] v, int len) { int i; for (i = 0; i < len; i++) { if (v[i] == 'e') break; } char[] tmp = new char[i]; System.arraycopy(v, 0, tmp, 0, i); return tmp; } private char[] exponent(char[] v, int len) { int i; for (i = len - 1; i >= 0; i--) { if (v[i] == 'e') break; } if (i == -1) return null; char[] tmp = new char[len - i - 1]; System.arraycopy(v, i + 1, tmp, 0, len - i - 1); return tmp; } // Add zeros to the requested precision. private char[] addZeros(char[] v, int prec) { // Look for the dot. If we don't find one, the we'll need to add // it before we add the zeros. int i; for (i = 0; i < v.length; i++) { if (v[i] == '.') break; } boolean needDot = false; if (i == v.length) { needDot = true; } // Determine existing precision. int outPrec = v.length - i - (needDot ? 0 : 1); assert (outPrec <= prec); if (outPrec == prec) return v; // Create new array with existing contents. char[] tmp = new char[v.length + prec - outPrec + (needDot ? 1 : 0)]; System.arraycopy(v, 0, tmp, 0, v.length); // Add dot if previously determined to be necessary. int start = v.length; if (needDot) { tmp[v.length] = '.'; start++; } // Add zeros. for (int j = start; j < tmp.length; j++) tmp[j] = '0'; return tmp; } // Method assumes that d > 0. private String hexDouble(double d, int prec) { // Let Double.toHexString handle simple cases if(!FpUtils.isFinite(d) || d == 0.0 || prec == 0 || prec >= 13) // remove "0x" return Double.toHexString(d).substring(2); else { assert(prec >= 1 && prec <= 12); int exponent = FpUtils.getExponent(d); boolean subnormal = (exponent == DoubleConsts.MIN_EXPONENT - 1); // If this is subnormal input so normalize (could be faster to // do as integer operation). if (subnormal) { scaleUp = FpUtils.scalb(1.0, 54); d *= scaleUp; // Calculate the exponent. This is not just exponent + 54 // since the former is not the normalized exponent. exponent = FpUtils.getExponent(d); assert exponent >= DoubleConsts.MIN_EXPONENT && exponent <= DoubleConsts.MAX_EXPONENT: exponent; } int precision = 1 + prec*4; int shiftDistance = DoubleConsts.SIGNIFICAND_WIDTH - precision; assert(shiftDistance >= 1 && shiftDistance < DoubleConsts.SIGNIFICAND_WIDTH); long doppel = Double.doubleToLongBits(d); // Deterime the number of bits to keep. long newSignif = (doppel & (DoubleConsts.EXP_BIT_MASK | DoubleConsts.SIGNIF_BIT_MASK)) >> shiftDistance; // Bits to round away. long roundingBits = doppel & ~(~0L << shiftDistance); // To decide how to round, look at the low-order bit of the // working significand, the highest order discarded bit (the // round bit) and whether any of the lower order discarded bits // are nonzero (the sticky bit). boolean leastZero = (newSignif & 0x1L) == 0L; boolean round = ((1L << (shiftDistance - 1) ) & roundingBits) != 0L; boolean sticky = shiftDistance > 1 && (~(1L<< (shiftDistance - 1)) & roundingBits) != 0; if((leastZero && round && sticky) || (!leastZero && round)) { newSignif++; } long signBit = doppel & DoubleConsts.SIGN_BIT_MASK; newSignif = signBit | (newSignif << shiftDistance); double result = Double.longBitsToDouble(newSignif); if (Double.isInfinite(result) ) { // Infinite result generated by rounding return "1.0p1024"; } else { String res = Double.toHexString(result).substring(2); if (!subnormal) return res; else { // Create a normalized subnormal string. int idx = res.indexOf('p'); if (idx == -1) { // No 'p' character in hex string. assert false; return null; } else { // Get exponent and append at the end. String exp = res.substring(idx + 1); int iexp = Integer.parseInt(exp) -54; return res.substring(0, idx) + "p" + Integer.toString(iexp); } } } } } private void print(BigDecimal value, Locale l) throws IOException { if (c == Conversion.HEXADECIMAL_FLOAT) failConversion(c, value); StringBuilder sb = new StringBuilder(); boolean neg = value.signum() == -1; BigDecimal v = value.abs(); // leading sign indicator leadingSign(sb, neg); // the value print(sb, v, l, f, c, precision, neg); // trailing sign indicator trailingSign(sb, neg); // justify based on width a.append(justify(sb.toString())); } // value > 0 private void print(StringBuilder sb, BigDecimal value, Locale l, Flags f, char c, int precision, boolean neg) throws IOException { if (c == Conversion.SCIENTIFIC) { // Create a new BigDecimal with the desired precision. int prec = (precision == -1 ? 6 : precision); int scale = value.scale(); int origPrec = value.precision(); int nzeros = 0; int compPrec; if (prec > origPrec - 1) { compPrec = origPrec; nzeros = prec - (origPrec - 1); } else { compPrec = prec + 1; } MathContext mc = new MathContext(compPrec); BigDecimal v = new BigDecimal(value.unscaledValue(), scale, mc); BigDecimalLayout bdl = new BigDecimalLayout(v.unscaledValue(), v.scale(), BigDecimalLayoutForm.SCIENTIFIC); char[] mant = bdl.mantissa(); // Add a decimal point if necessary. The mantissa may not // contain a decimal point if the scale is zero (the internal // representation has no fractional part) or the original // precision is one. Append a decimal point if '#' is set or if // we require zero padding to get to the requested precision. if ((origPrec == 1 || !bdl.hasDot()) && (nzeros > 0 || (f.contains(Flags.ALTERNATE)))) mant = addDot(mant); // Add trailing zeros in the case precision is greater than // the number of available digits after the decimal separator. mant = trailingZeros(mant, nzeros); char[] exp = bdl.exponent(); int newW = width; if (width != -1) newW = adjustWidth(width - exp.length - 1, f, neg); localizedMagnitude(sb, mant, f, newW, l); sb.append(f.contains(Flags.UPPERCASE) ? 'E' : 'e'); Flags flags = f.dup().remove(Flags.GROUP); char sign = exp[0]; assert(sign == '+' || sign == '-'); sb.append(exp[0]); char[] tmp = new char[exp.length - 1]; System.arraycopy(exp, 1, tmp, 0, exp.length - 1); sb.append(localizedMagnitude(null, tmp, flags, -1, l)); } else if (c == Conversion.DECIMAL_FLOAT) { // Create a new BigDecimal with the desired precision. int prec = (precision == -1 ? 6 : precision); int scale = value.scale(); int compPrec = value.precision(); if (scale > prec) compPrec -= (scale - prec); MathContext mc = new MathContext(compPrec); BigDecimal v = new BigDecimal(value.unscaledValue(), scale, mc); BigDecimalLayout bdl = new BigDecimalLayout(v.unscaledValue(), v.scale(), BigDecimalLayoutForm.DECIMAL_FLOAT); char mant[] = bdl.mantissa(); int nzeros = (bdl.scale() < prec ? prec - bdl.scale() : 0); // Add a decimal point if necessary. The mantissa may not // contain a decimal point if the scale is zero (the internal // representation has no fractional part). Append a decimal // point if '#' is set or we require zero padding to get to the // requested precision. if (bdl.scale() == 0 && (f.contains(Flags.ALTERNATE) || nzeros > 0)) mant = addDot(bdl.mantissa()); // Add trailing zeros if the precision is greater than the // number of available digits after the decimal separator. mant = trailingZeros(mant, nzeros); localizedMagnitude(sb, mant, f, adjustWidth(width, f, neg), l); } else if (c == Conversion.GENERAL) { int prec = precision; if (precision == -1) prec = 6; else if (precision == 0) prec = 1; BigDecimal tenToTheNegFour = BigDecimal.valueOf(1, 4); BigDecimal tenToThePrec = BigDecimal.valueOf(1, -prec); if ((value.equals(BigDecimal.ZERO)) || ((value.compareTo(tenToTheNegFour) != -1) && (value.compareTo(tenToThePrec) == -1))) { int e = - value.scale() + (value.unscaledValue().toString().length() - 1); // xxx.yyy // g precision (# sig digits) = #x + #y // f precision = #y // exponent = #x - 1 // => f precision = g precision - exponent - 1 // 0.000zzz // g precision (# sig digits) = #z // f precision = #0 (after '.') + #z // exponent = - #0 (after '.') - 1 // => f precision = g precision - exponent - 1 prec = prec - e - 1; print(sb, value, l, f, Conversion.DECIMAL_FLOAT, prec, neg); } else { print(sb, value, l, f, Conversion.SCIENTIFIC, prec - 1, neg); } } else if (c == Conversion.HEXADECIMAL_FLOAT) { // This conversion isn't supported. The error should be // reported earlier. assert false; } } private class BigDecimalLayout { private StringBuilder mant; private StringBuilder exp; private boolean dot = false; private int scale; public BigDecimalLayout(BigInteger intVal, int scale, BigDecimalLayoutForm form) { layout(intVal, scale, form); } public boolean hasDot() { return dot; } public int scale() { return scale; } // char[] with canonical string representation public char[] layoutChars() { StringBuilder sb = new StringBuilder(mant); if (exp != null) { sb.append('E'); sb.append(exp); } return toCharArray(sb); } public char[] mantissa() { return toCharArray(mant); } // The exponent will be formatted as a sign ('+' or '-') followed // by the exponent zero-padded to include at least two digits. public char[] exponent() { return toCharArray(exp); } private char[] toCharArray(StringBuilder sb) { if (sb == null) return null; char[] result = new char[sb.length()]; sb.getChars(0, result.length, result, 0); return result; } private void layout(BigInteger intVal, int scale, BigDecimalLayoutForm form) { char coeff[] = intVal.toString().toCharArray(); this.scale = scale; // Construct a buffer, with sufficient capacity for all cases. // If E-notation is needed, length will be: +1 if negative, +1 // if '.' needed, +2 for "E+", + up to 10 for adjusted // exponent. Otherwise it could have +1 if negative, plus // leading "0.00000" mant = new StringBuilder(coeff.length + 14); if (scale == 0) { int len = coeff.length; if (len > 1) { mant.append(coeff[0]); if (form == BigDecimalLayoutForm.SCIENTIFIC) { mant.append('.'); dot = true; mant.append(coeff, 1, len - 1); exp = new StringBuilder("+"); if (len < 10) exp.append("0").append(len - 1); else exp.append(len - 1); } else { mant.append(coeff, 1, len - 1); } } else { mant.append(coeff); if (form == BigDecimalLayoutForm.SCIENTIFIC) exp = new StringBuilder("+00"); } return; } long adjusted = -(long) scale + (coeff.length - 1); if (form == BigDecimalLayoutForm.DECIMAL_FLOAT) { // count of padding zeros int pad = scale - coeff.length; if (pad >= 0) { // 0.xxx form mant.append("0."); dot = true; for (; pad > 0 ; pad--) mant.append('0'); mant.append(coeff); } else { if (-pad < coeff.length) { // xx.xx form mant.append(coeff, 0, -pad); mant.append('.'); dot = true; mant.append(coeff, -pad, scale); } else { // xx form mant.append(coeff, 0, coeff.length); for (int i = 0; i < -scale; i++) mant.append('0'); this.scale = 0; } } } else { // x.xxx form mant.append(coeff[0]); if (coeff.length > 1) { mant.append('.'); dot = true; mant.append(coeff, 1, coeff.length-1); } exp = new StringBuilder(); if (adjusted != 0) { long abs = Math.abs(adjusted); // require sign exp.append(adjusted < 0 ? '-' : '+'); if (abs < 10) exp.append('0'); exp.append(abs); } else { exp.append("+00"); } } } } private int adjustWidth(int width, Flags f, boolean neg) { int newW = width; if (newW != -1 && neg && f.contains(Flags.PARENTHESES)) newW--; return newW; } // Add a '.' to th mantissa if required private char[] addDot(char[] mant) { char[] tmp = mant; tmp = new char[mant.length + 1]; System.arraycopy(mant, 0, tmp, 0, mant.length); tmp[tmp.length - 1] = '.'; return tmp; } // Add trailing zeros in the case precision is greater than the number // of available digits after the decimal separator. private char[] trailingZeros(char[] mant, int nzeros) { char[] tmp = mant; if (nzeros > 0) { tmp = new char[mant.length + nzeros]; System.arraycopy(mant, 0, tmp, 0, mant.length); for (int i = mant.length; i < tmp.length; i++) tmp[i] = '0'; } return tmp; } private void print(Calendar t, char c, Locale l) throws IOException { StringBuilder sb = new StringBuilder(); print(sb, t, c, l); // justify based on width String s = justify(sb.toString()); if (f.contains(Flags.UPPERCASE)) s = s.toUpperCase(); a.append(s); } private Appendable print(StringBuilder sb, Calendar t, char c, Locale l) throws IOException { assert(width == -1); if (sb == null) sb = new StringBuilder(); switch (c) { case DateTime.HOUR_OF_DAY_0: // 'H' (00 - 23) case DateTime.HOUR_0: // 'I' (01 - 12) case DateTime.HOUR_OF_DAY: // 'k' (0 - 23) -- like H case DateTime.HOUR: { // 'l' (1 - 12) -- like I int i = t.get(Calendar.HOUR_OF_DAY); if (c == DateTime.HOUR_0 || c == DateTime.HOUR) i = (i == 0 || i == 12 ? 12 : i % 12); Flags flags = (c == DateTime.HOUR_OF_DAY_0 || c == DateTime.HOUR_0 ? Flags.ZERO_PAD : Flags.NONE); sb.append(localizedMagnitude(null, i, flags, 2, l)); break; } case DateTime.MINUTE: { // 'M' (00 - 59) int i = t.get(Calendar.MINUTE); Flags flags = Flags.ZERO_PAD; sb.append(localizedMagnitude(null, i, flags, 2, l)); break; } case DateTime.NANOSECOND: { // 'N' (000000000 - 999999999) int i = t.get(Calendar.MILLISECOND) * 1000000; Flags flags = Flags.ZERO_PAD; sb.append(localizedMagnitude(null, i, flags, 9, l)); break; } case DateTime.MILLISECOND: { // 'L' (000 - 999) int i = t.get(Calendar.MILLISECOND); Flags flags = Flags.ZERO_PAD; sb.append(localizedMagnitude(null, i, flags, 3, l)); break; } case DateTime.MILLISECOND_SINCE_EPOCH: { // 'Q' (0 - 99...?) long i = t.getTimeInMillis(); Flags flags = Flags.NONE; sb.append(localizedMagnitude(null, i, flags, width, l)); break; } case DateTime.AM_PM: { // 'p' (am or pm) // Calendar.AM = 0, Calendar.PM = 1, LocaleElements defines upper String[] ampm = { "AM", "PM" }; if (l != null && l != Locale.US) { DateFormatSymbols dfs = DateFormatSymbols.getInstance(l); ampm = dfs.getAmPmStrings(); } String s = ampm[t.get(Calendar.AM_PM)]; sb.append(s.toLowerCase(l != null ? l : Locale.US)); break; } case DateTime.SECONDS_SINCE_EPOCH: { // 's' (0 - 99...?) long i = t.getTimeInMillis() / 1000; Flags flags = Flags.NONE; sb.append(localizedMagnitude(null, i, flags, width, l)); break; } case DateTime.SECOND: { // 'S' (00 - 60 - leap second) int i = t.get(Calendar.SECOND); Flags flags = Flags.ZERO_PAD; sb.append(localizedMagnitude(null, i, flags, 2, l)); break; } case DateTime.ZONE_NUMERIC: { // 'z' ({-|+}####) - ls minus? int i = t.get(Calendar.ZONE_OFFSET) + t.get(Calendar.DST_OFFSET); boolean neg = i < 0; sb.append(neg ? '-' : '+'); if (neg) i = -i; int min = i / 60000; // combine minute and hour into a single integer int offset = (min / 60) * 100 + (min % 60); Flags flags = Flags.ZERO_PAD; sb.append(localizedMagnitude(null, offset, flags, 4, l)); break; } case DateTime.ZONE: { // 'Z' (symbol) TimeZone tz = t.getTimeZone(); sb.append(tz.getDisplayName((t.get(Calendar.DST_OFFSET) != 0), TimeZone.SHORT, (l == null) ? Locale.US : l)); break; } // Date case DateTime.NAME_OF_DAY_ABBREV: // 'a' case DateTime.NAME_OF_DAY: { // 'A' int i = t.get(Calendar.DAY_OF_WEEK); Locale lt = ((l == null) ? Locale.US : l); DateFormatSymbols dfs = DateFormatSymbols.getInstance(lt); if (c == DateTime.NAME_OF_DAY) sb.append(dfs.getWeekdays()[i]); else sb.append(dfs.getShortWeekdays()[i]); break; } case DateTime.NAME_OF_MONTH_ABBREV: // 'b' case DateTime.NAME_OF_MONTH_ABBREV_X: // 'h' -- same b case DateTime.NAME_OF_MONTH: { // 'B' int i = t.get(Calendar.MONTH); Locale lt = ((l == null) ? Locale.US : l); DateFormatSymbols dfs = DateFormatSymbols.getInstance(lt); if (c == DateTime.NAME_OF_MONTH) sb.append(dfs.getMonths()[i]); else sb.append(dfs.getShortMonths()[i]); break; } case DateTime.CENTURY: // 'C' (00 - 99) case DateTime.YEAR_2: // 'y' (00 - 99) case DateTime.YEAR_4: { // 'Y' (0000 - 9999) int i = t.get(Calendar.YEAR); int size = 2; switch (c) { case DateTime.CENTURY: i /= 100; break; case DateTime.YEAR_2: i %= 100; break; case DateTime.YEAR_4: size = 4; break; } Flags flags = Flags.ZERO_PAD; sb.append(localizedMagnitude(null, i, flags, size, l)); break; } case DateTime.DAY_OF_MONTH_0: // 'd' (01 - 31) case DateTime.DAY_OF_MONTH: { // 'e' (1 - 31) -- like d int i = t.get(Calendar.DATE); Flags flags = (c == DateTime.DAY_OF_MONTH_0 ? Flags.ZERO_PAD : Flags.NONE); sb.append(localizedMagnitude(null, i, flags, 2, l)); break; } case DateTime.DAY_OF_YEAR: { // 'j' (001 - 366) int i = t.get(Calendar.DAY_OF_YEAR); Flags flags = Flags.ZERO_PAD; sb.append(localizedMagnitude(null, i, flags, 3, l)); break; } case DateTime.MONTH: { // 'm' (01 - 12) int i = t.get(Calendar.MONTH) + 1; Flags flags = Flags.ZERO_PAD; sb.append(localizedMagnitude(null, i, flags, 2, l)); break; } // Composites case DateTime.TIME: // 'T' (24 hour hh:mm:ss - %tH:%tM:%tS) case DateTime.TIME_24_HOUR: { // 'R' (hh:mm same as %H:%M) char sep = ':'; print(sb, t, DateTime.HOUR_OF_DAY_0, l).append(sep); print(sb, t, DateTime.MINUTE, l); if (c == DateTime.TIME) { sb.append(sep); print(sb, t, DateTime.SECOND, l); } break; } case DateTime.TIME_12_HOUR: { // 'r' (hh:mm:ss [AP]M) char sep = ':'; print(sb, t, DateTime.HOUR_0, l).append(sep); print(sb, t, DateTime.MINUTE, l).append(sep); print(sb, t, DateTime.SECOND, l).append(' '); // this may be in wrong place for some locales StringBuilder tsb = new StringBuilder(); print(tsb, t, DateTime.AM_PM, l); sb.append(tsb.toString().toUpperCase(l != null ? l : Locale.US)); break; } case DateTime.DATE_TIME: { // 'c' (Sat Nov 04 12:02:33 EST 1999) char sep = ' '; print(sb, t, DateTime.NAME_OF_DAY_ABBREV, l).append(sep); print(sb, t, DateTime.NAME_OF_MONTH_ABBREV, l).append(sep); print(sb, t, DateTime.DAY_OF_MONTH_0, l).append(sep); print(sb, t, DateTime.TIME, l).append(sep); print(sb, t, DateTime.ZONE, l).append(sep); print(sb, t, DateTime.YEAR_4, l); break; } case DateTime.DATE: { // 'D' (mm/dd/yy) char sep = '/'; print(sb, t, DateTime.MONTH, l).append(sep); print(sb, t, DateTime.DAY_OF_MONTH_0, l).append(sep); print(sb, t, DateTime.YEAR_2, l); break; } case DateTime.ISO_STANDARD_DATE: { // 'F' (%Y-%m-%d) char sep = '-'; print(sb, t, DateTime.YEAR_4, l).append(sep); print(sb, t, DateTime.MONTH, l).append(sep); print(sb, t, DateTime.DAY_OF_MONTH_0, l); break; } default: assert false; } return sb; } // -- Methods to support throwing exceptions -- private void failMismatch(Flags f, char c) { String fs = f.toString(); throw new FormatFlagsConversionMismatchException(fs, c); } private void failConversion(char c, Object arg) { throw new IllegalFormatConversionException(c, arg.getClass()); } private char getZero(Locale l) { if ((l != null) && !l.equals(locale())) { DecimalFormatSymbols dfs = DecimalFormatSymbols.getInstance(l); return dfs.getZeroDigit(); } return zero; } private StringBuilder localizedMagnitude(StringBuilder sb, long value, Flags f, int width, Locale l) { char[] va = Long.toString(value, 10).toCharArray(); return localizedMagnitude(sb, va, f, width, l); } private StringBuilder localizedMagnitude(StringBuilder sb, char[] value, Flags f, int width, Locale l) { if (sb == null) sb = new StringBuilder(); int begin = sb.length(); char zero = getZero(l); // determine localized grouping separator and size char grpSep = '\0'; int grpSize = -1; char decSep = '\0'; int len = value.length; int dot = len; for (int j = 0; j < len; j++) { if (value[j] == '.') { dot = j; break; } } if (dot < len) { if (l == null || l.equals(Locale.US)) { decSep = '.'; } else { DecimalFormatSymbols dfs = DecimalFormatSymbols.getInstance(l); decSep = dfs.getDecimalSeparator(); } } if (f.contains(Flags.GROUP)) { if (l == null || l.equals(Locale.US)) { grpSep = ','; grpSize = 3; } else { DecimalFormatSymbols dfs = DecimalFormatSymbols.getInstance(l); grpSep = dfs.getGroupingSeparator(); DecimalFormat df = (DecimalFormat) NumberFormat.getIntegerInstance(l); grpSize = df.getGroupingSize(); } } // localize the digits inserting group separators as necessary for (int j = 0; j < len; j++) { if (j == dot) { sb.append(decSep); // no more group separators after the decimal separator grpSep = '\0'; continue; } char c = value[j]; sb.append((char) ((c - '0') + zero)); if (grpSep != '\0' && j != dot - 1 && ((dot - j) % grpSize == 1)) sb.append(grpSep); } // apply zero padding len = sb.length(); if (width != -1 && f.contains(Flags.ZERO_PAD)) for (int k = 0; k < width - len; k++) sb.insert(begin, zero); return sb; } } private static class Flags { private int flags; static final Flags NONE = new Flags(0); // '' // duplicate declarations from Formattable.java static final Flags LEFT_JUSTIFY = new Flags(1<<0); // '-' static final Flags UPPERCASE = new Flags(1<<1); // '^' static final Flags ALTERNATE = new Flags(1<<2); // '#' // numerics static final Flags PLUS = new Flags(1<<3); // '+' static final Flags LEADING_SPACE = new Flags(1<<4); // ' ' static final Flags ZERO_PAD = new Flags(1<<5); // '0' static final Flags GROUP = new Flags(1<<6); // ',' static final Flags PARENTHESES = new Flags(1<<7); // '(' // indexing static final Flags PREVIOUS = new Flags(1<<8); // '<' private Flags(int f) { flags = f; } public int valueOf() { return flags; } public boolean contains(Flags f) { return (flags & f.valueOf()) == f.valueOf(); } public Flags dup() { return new Flags(flags); } private Flags add(Flags f) { flags |= f.valueOf(); return this; } public Flags remove(Flags f) { flags &= ~f.valueOf(); return this; } public static Flags parse(String s) { char[] ca = s.toCharArray(); Flags f = new Flags(0); for (int i = 0; i < ca.length; i++) { Flags v = parse(ca[i]); if (f.contains(v)) throw new DuplicateFormatFlagsException(v.toString()); f.add(v); } return f; } // parse those flags which may be provided by users private static Flags parse(char c) { switch (c) { case '-': return LEFT_JUSTIFY; case '#': return ALTERNATE; case '+': return PLUS; case ' ': return LEADING_SPACE; case '0': return ZERO_PAD; case ',': return GROUP; case '(': return PARENTHESES; case '<': return PREVIOUS; default: throw new UnknownFormatFlagsException(String.valueOf(c)); } } // Returns a string representation of the current <tt>Flags</tt>. public static String toString(Flags f) { return f.toString(); } public String toString() { StringBuilder sb = new StringBuilder(); if (contains(LEFT_JUSTIFY)) sb.append('-'); if (contains(UPPERCASE)) sb.append('^'); if (contains(ALTERNATE)) sb.append('#'); if (contains(PLUS)) sb.append('+'); if (contains(LEADING_SPACE)) sb.append(' '); if (contains(ZERO_PAD)) sb.append('0'); if (contains(GROUP)) sb.append(','); if (contains(PARENTHESES)) sb.append('('); if (contains(PREVIOUS)) sb.append('<'); return sb.toString(); } } private static class Conversion { // Byte, Short, Integer, Long, BigInteger // (and associated primitives due to autoboxing) static final char DECIMAL_INTEGER = 'd'; static final char OCTAL_INTEGER = 'o'; static final char HEXADECIMAL_INTEGER = 'x'; static final char HEXADECIMAL_INTEGER_UPPER = 'X'; // Float, Double, BigDecimal // (and associated primitives due to autoboxing) static final char SCIENTIFIC = 'e'; static final char SCIENTIFIC_UPPER = 'E'; static final char GENERAL = 'g'; static final char GENERAL_UPPER = 'G'; static final char DECIMAL_FLOAT = 'f'; static final char HEXADECIMAL_FLOAT = 'a'; static final char HEXADECIMAL_FLOAT_UPPER = 'A'; // Character, Byte, Short, Integer // (and associated primitives due to autoboxing) static final char CHARACTER = 'c'; static final char CHARACTER_UPPER = 'C'; // java.util.Date, java.util.Calendar, long static final char DATE_TIME = 't'; static final char DATE_TIME_UPPER = 'T'; // if (arg.TYPE != boolean) return boolean // if (arg != null) return true; else return false; static final char BOOLEAN = 'b'; static final char BOOLEAN_UPPER = 'B'; // if (arg instanceof Formattable) arg.formatTo() // else arg.toString(); static final char STRING = 's'; static final char STRING_UPPER = 'S'; // arg.hashCode() static final char HASHCODE = 'h'; static final char HASHCODE_UPPER = 'H'; static final char LINE_SEPARATOR = 'n'; static final char PERCENT_SIGN = '%'; static boolean isValid(char c) { return (isGeneral(c) || isInteger(c) || isFloat(c) || isText(c) || c == 't' || isCharacter(c)); } // Returns true iff the Conversion is applicable to all objects. static boolean isGeneral(char c) { switch (c) { case BOOLEAN: case BOOLEAN_UPPER: case STRING: case STRING_UPPER: case HASHCODE: case HASHCODE_UPPER: return true; default: return false; } } // Returns true iff the Conversion is applicable to character. static boolean isCharacter(char c) { switch (c) { case CHARACTER: case CHARACTER_UPPER: return true; default: return false; } } // Returns true iff the Conversion is an integer type. static boolean isInteger(char c) { switch (c) { case DECIMAL_INTEGER: case OCTAL_INTEGER: case HEXADECIMAL_INTEGER: case HEXADECIMAL_INTEGER_UPPER: return true; default: return false; } } // Returns true iff the Conversion is a floating-point type. static boolean isFloat(char c) { switch (c) { case SCIENTIFIC: case SCIENTIFIC_UPPER: case GENERAL: case GENERAL_UPPER: case DECIMAL_FLOAT: case HEXADECIMAL_FLOAT: case HEXADECIMAL_FLOAT_UPPER: return true; default: return false; } } // Returns true iff the Conversion does not require an argument static boolean isText(char c) { switch (c) { case LINE_SEPARATOR: case PERCENT_SIGN: return true; default: return false; } } } private static class DateTime { static final char HOUR_OF_DAY_0 = 'H'; // (00 - 23) static final char HOUR_0 = 'I'; // (01 - 12) static final char HOUR_OF_DAY = 'k'; // (0 - 23) -- like H static final char HOUR = 'l'; // (1 - 12) -- like I static final char MINUTE = 'M'; // (00 - 59) static final char NANOSECOND = 'N'; // (000000000 - 999999999) static final char MILLISECOND = 'L'; // jdk, not in gnu (000 - 999) static final char MILLISECOND_SINCE_EPOCH = 'Q'; // (0 - 99...?) static final char AM_PM = 'p'; // (am or pm) static final char SECONDS_SINCE_EPOCH = 's'; // (0 - 99...?) static final char SECOND = 'S'; // (00 - 60 - leap second) static final char TIME = 'T'; // (24 hour hh:mm:ss) static final char ZONE_NUMERIC = 'z'; // (-1200 - +1200) - ls minus? static final char ZONE = 'Z'; // (symbol) // Date static final char NAME_OF_DAY_ABBREV = 'a'; // 'a' static final char NAME_OF_DAY = 'A'; // 'A' static final char NAME_OF_MONTH_ABBREV = 'b'; // 'b' static final char NAME_OF_MONTH = 'B'; // 'B' static final char CENTURY = 'C'; // (00 - 99) static final char DAY_OF_MONTH_0 = 'd'; // (01 - 31) static final char DAY_OF_MONTH = 'e'; // (1 - 31) -- like d // * static final char ISO_WEEK_OF_YEAR_2 = 'g'; // cross %y %V // * static final char ISO_WEEK_OF_YEAR_4 = 'G'; // cross %Y %V static final char NAME_OF_MONTH_ABBREV_X = 'h'; // -- same b static final char DAY_OF_YEAR = 'j'; // (001 - 366) static final char MONTH = 'm'; // (01 - 12) // * static final char DAY_OF_WEEK_1 = 'u'; // (1 - 7) Monday // * static final char WEEK_OF_YEAR_SUNDAY = 'U'; // (0 - 53) Sunday+ // * static final char WEEK_OF_YEAR_MONDAY_01 = 'V'; // (01 - 53) Monday+ // * static final char DAY_OF_WEEK_0 = 'w'; // (0 - 6) Sunday // * static final char WEEK_OF_YEAR_MONDAY = 'W'; // (00 - 53) Monday static final char YEAR_2 = 'y'; // (00 - 99) static final char YEAR_4 = 'Y'; // (0000 - 9999) // Composites static final char TIME_12_HOUR = 'r'; // (hh:mm:ss [AP]M) static final char TIME_24_HOUR = 'R'; // (hh:mm same as %H:%M) // * static final char LOCALE_TIME = 'X'; // (%H:%M:%S) - parse format? static final char DATE_TIME = 'c'; // (Sat Nov 04 12:02:33 EST 1999) static final char DATE = 'D'; // (mm/dd/yy) static final char ISO_STANDARD_DATE = 'F'; // (%Y-%m-%d) // * static final char LOCALE_DATE = 'x'; // (mm/dd/yy) static boolean isValid(char c) { switch (c) { case HOUR_OF_DAY_0: case HOUR_0: case HOUR_OF_DAY: case HOUR: case MINUTE: case NANOSECOND: case MILLISECOND: case MILLISECOND_SINCE_EPOCH: case AM_PM: case SECONDS_SINCE_EPOCH: case SECOND: case TIME: case ZONE_NUMERIC: case ZONE: // Date case NAME_OF_DAY_ABBREV: case NAME_OF_DAY: case NAME_OF_MONTH_ABBREV: case NAME_OF_MONTH: case CENTURY: case DAY_OF_MONTH_0: case DAY_OF_MONTH: // * case ISO_WEEK_OF_YEAR_2: // * case ISO_WEEK_OF_YEAR_4: case NAME_OF_MONTH_ABBREV_X: case DAY_OF_YEAR: case MONTH: // * case DAY_OF_WEEK_1: // * case WEEK_OF_YEAR_SUNDAY: // * case WEEK_OF_YEAR_MONDAY_01: // * case DAY_OF_WEEK_0: // * case WEEK_OF_YEAR_MONDAY: case YEAR_2: case YEAR_4: // Composites case TIME_12_HOUR: case TIME_24_HOUR: // * case LOCALE_TIME: case DATE_TIME: case DATE: case ISO_STANDARD_DATE: // * case LOCALE_DATE: return true; default: return false; } } } }