/* * * * Copyright 1990-2009 Sun Microsystems, Inc. All Rights Reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER * * This program 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. * * This program 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 at /legal/license.txt). * * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa * Clara, CA 95054 or visit www.sun.com if you need additional * information or have any questions. */ package java.lang; /** * The Long class wraps a value of the primitive type <code>long</code> * in an object. An object of type <code>Long</code> contains a single * field whose type is <code>long</code>. * <p> * In addition, this class provides several methods for converting a * <code>long</code> to a <code>String</code> and a * <code>String</code> to a <code>long</code>, as well as other * constants and methods useful when dealing with a * <code>long</code>. * * @version 12/17/01 (CLDC 1.1) * @since JDK1.0, CLDC 1.0 */ public final class Long { /** * The smallest value of type <code>long</code>. */ public static final long MIN_VALUE = 0x8000000000000000L; /** * The largest value of type <code>long</code>. */ public static final long MAX_VALUE = 0x7fffffffffffffffL; /** * Creates a string representation of the first argument in the * radix specified by the second argument. * <p> * If the radix is smaller than <code>Character.MIN_RADIX</code> or * larger than <code>Character.MAX_RADIX</code>, then the radix * <code>10</code> is used instead. * <p> * If the first argument is negative, the first element of the * result is the ASCII minus sign <code>'-'</code> * (<code>'\u002d'</code>. If the first argument is not negative, * no sign character appears in the result. * <p> * The remaining characters of the result represent the magnitude of * the first argument. If the magnitude is zero, it is represented by * a single zero character <code>'0'</code> * (<code>'\u0030'</code>); otherwise, the first character of the * representation of the magnitude will not be the zero character. * The following ASCII characters are used as digits: * <blockquote><pre> * 0123456789abcdefghijklmnopqrstuvwxyz * </pre></blockquote> * These are <tt>'\u0030'</tt> through <tt>'\u0039'</tt> * and <tt>'\u0061'</tt> through <tt>'\u007a'</tt>. If the * radix is <var>N</var>, then the first <var>N</var> of these * characters are used as radix-<var>N</var> digits in the order * shown. Thus, the digits for hexadecimal (radix 16) are * <blockquote><pre> * <tt>0123456789abcdef</tt>. * </pre></blockquote> * * @param i a long. * @param radix the radix. * @return a string representation of the argument in the specified radix. * @see java.lang.Character#MAX_RADIX * @see java.lang.Character#MIN_RADIX */ public static String toString(long i, int radix) { if (radix < Character.MIN_RADIX || radix > Character.MAX_RADIX) radix = 10; char[] buf = new char[65]; int charPos = 64; boolean negative = (i < 0); if (!negative) { i = -i; } while (i <= -radix) { buf[charPos--] = Integer.digits[(int)(-(i % radix))]; i = i / radix; } buf[charPos] = Integer.digits[(int)(-i)]; if (negative) { buf[--charPos] = '-'; } return new String(buf, charPos, (65 - charPos)); } /** * Returns a new String object representing the specified integer. * The argument is converted to signed decimal representation and * returned as a string, exactly as if the argument and the radix * 10 were given as arguments to the * {@link #toString(long, int)} method that takes two arguments. * * @param i a <code>long</code> to be converted. * @return a string representation of the argument in base 10. */ public static String toString(long i) { return toString(i, 10); } /** * Parses the string argument as a signed <code>long</code> in the * radix specified by the second argument. The characters in the * string must all be digits of the specified radix (as determined by * whether <code>Character.digit</code> returns a * nonnegative value), except that the first character may be an * ASCII minus sign <code>'-'</code> (<tt>'\u002d'</tt> to indicate * a negative value. The resulting <code>long</code> value is returned. * <p> * Note that neither <tt>L</tt> nor <tt>l</tt> is permitted to appear at * the end of the string as a type indicator, as would be permitted in * Java programming language source code - except that either <tt>L</tt> * or <tt>l</tt> may appear as a digit for a radix greater than 22. * <p> * An exception of type <tt>NumberFormatException</tt> is thrown if any of * the following situations occurs: * <ul> * <li>The first argument is <tt>null</tt> or is a string of length zero. * <li>The <tt>radix</tt> is either smaller than * {@link java.lang.Character#MIN_RADIX} or larger than * {@link java.lang.Character#MAX_RADIX}. * <li>The first character of the string is not a digit of the * specified <tt>radix</tt> and is not a minus sign <tt>'-'</tt> * (<tt>'\u002d'</tt>). * <li>The first character of the string is a minus sign and the * string is of length 1. * <li>Any character of the string after the first is not a digit of * the specified <tt>radix</tt>. * <li>The integer value represented by the string cannot be * represented as a value of type <tt>long</tt>. * </ul><p> * Examples: * <blockquote><pre> * parseLong("0", 10) returns 0L * parseLong("473", 10) returns 473L * parseLong("-0", 10) returns 0L * parseLong("-FF", 16) returns -255L * parseLong("1100110", 2) returns 102L * parseLong("99", 8) throws a NumberFormatException * parseLong("Hazelnut", 10) throws a NumberFormatException * parseLong("Hazelnut", 36) returns 1356099454469L * </pre></blockquote> * * @param s the <code>String</code> containing the * <code>long</code>. * @param radix the radix to be used. * @return the <code>long</code> represented by the string argument in * the specified radix. * @exception NumberFormatException if the string does not contain a * parsable integer. */ public static long parseLong(String s, int radix) throws NumberFormatException { if (s == null) { throw new NumberFormatException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped "null" /* #endif */ ); } if (radix < Character.MIN_RADIX) { throw new NumberFormatException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped "radix " + radix + /// skipped " less than Character.MIN_RADIX" /* #endif */ ); } if (radix > Character.MAX_RADIX) { throw new NumberFormatException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped "radix " + radix + /// skipped " greater than Character.MAX_RADIX" /* #endif */ ); } long result = 0; boolean negative = false; int i = 0, max = s.length(); long limit; long multmin; int digit; if (max > 0) { if (s.charAt(0) == '-') { negative = true; limit = Long.MIN_VALUE; i++; } else { limit = -Long.MAX_VALUE; } multmin = limit / radix; if (i < max) { digit = Character.digit(s.charAt(i++),radix); if (digit < 0) { throw new NumberFormatException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped s /* #endif */ ); } else { result = -digit; } } while (i < max) { // Accumulating negatively avoids surprises near MAX_VALUE digit = Character.digit(s.charAt(i++),radix); if (digit < 0) { throw new NumberFormatException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped s /* #endif */ ); } if (result < multmin) { throw new NumberFormatException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped s /* #endif */ ); } result *= radix; if (result < limit + digit) { throw new NumberFormatException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped s /* #endif */ ); } result -= digit; } } else { throw new NumberFormatException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped s /* #endif */ ); } if (negative) { if (i > 1) { return result; } else { /* Only got "-" */ throw new NumberFormatException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped s /* #endif */ ); } } else { return -result; } } /** * Parses the string argument as a signed decimal <code>long</code>. * The characters in the string must all be decimal digits, except * that the first character may be an ASCII minus sign * <code>'-'</code> (<code>\u002d'</code>) to indicate a negative * value. The resulting long value is returned, exactly as if the * argument and the radix <tt>10</tt> were given as arguments to the * {@link #parseLong(String, int)} method that takes two arguments. * <p> * Note that neither <tt>L</tt> nor <tt>l</tt> is permitted to appear * at the end of the string as a type indicator, as would be permitted * in Java programming language source code. * * @param s a string. * @return the <code>long</code> represented by the argument in decimal. * @exception NumberFormatException if the string does not contain a * parsable <code>long</code>. */ public static long parseLong(String s) throws NumberFormatException { return parseLong(s, 10); } /** * The value of the Long. */ private long value; /** * Constructs a newly allocated <code>Long</code> object that * represents the primitive <code>long</code> argument. * * @param value the value to be represented by the * <code>Long</code> object. */ public Long(long value) { this.value = value; } /** * Returns the value of this Long as a long value. * * @return the <code>long</code> value represented by this object. */ public long longValue() { return (long)value; } /** * Returns the value of this Long as a float. * * @return the <code>long</code> value represented by this object is * converted to type <code>float</code> and the result of * the conversion is returned. * @since CLDC 1.1 */ public float floatValue() { return (float)value; } /** * Returns the value of this Long as a double. * * @return the <code>long</code> value represented by this object that * is converted to type <code>double</code> and the result of * the conversion is returned. * @since CLDC 1.1 */ public double doubleValue() { return (double)value; } /** * Returns a String object representing this Long's value. * The long integer value represented by this Long object is converted * to signed decimal representation and returned as a string, exactly * as if the long value were given as an argument to the * {@link #toString(long)} method that takes one argument. * * @return a string representation of this object in base 10. */ public String toString() { return String.valueOf(value); } /** * Computes a hashcode for this Long. The result is the exclusive * OR of the two halves of the primitive <code>long</code> value * represented by this <code>Long</code> object. That is, the hashcode * is the value of the expression: * <blockquote><pre> * (int)(this.longValue()^(this.longValue()>>>32)) * </pre></blockquote> * * @return a hash code value for this object. */ public int hashCode() { return (int)(value ^ (value >> 32)); } /** * Compares this object against the specified object. * The result is <code>true</code> if and only if the argument is * not <code>null</code> and is a <code>Long</code> object that * contains the same <code>long</code> value as this object. * * @param obj the object to compare with. * @return <code>true</code> if the objects are the same; * <code>false</code> otherwise. */ public boolean equals(Object obj) { if (obj instanceof Long) { return value == ((Long)obj).longValue(); } return false; } }