/* * * * 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; import java.io.UnsupportedEncodingException; import com.sun.cldc.i18n.*; import com.sun.cldchi.jvm.JVM; /** * The <code>String</code> class represents character strings. All * string literals in Java programs, such as <code>"abc"</code>, are * implemented as instances of this class. * <p> * Strings are constant; their values cannot be changed after they * are created. String buffers support mutable strings. * Because String objects are immutable they can be shared. For example: * <p><blockquote><pre> * String str = "abc"; * </pre></blockquote><p> * is equivalent to: * <p><blockquote><pre> * char data[] = {'a', 'b', 'c'}; * String str = new String(data); * </pre></blockquote><p> * Here are some more examples of how strings can be used: * <p><blockquote><pre> * System.out.println("abc"); * String cde = "cde"; * System.out.println("abc" + cde); * String c = "abc".substring(2,3); * String d = cde.substring(1, 2); * </pre></blockquote> * <p> * The class <code>String</code> includes methods for examining * individual characters of the sequence, for comparing strings, for * searching strings, for extracting substrings, and for creating a * copy of a string with all characters translated to uppercase or to * lowercase. * <p> * The Java language provides special support for the string * concatenation operator ( + ), and for conversion of * other objects to strings. String concatenation is implemented * through the <code>StringBuffer</code> class and its * <code>append</code> method. * String conversions are implemented through the method * <code>toString</code>, defined by <code>Object</code> and * inherited by all classes in Java. For additional information on * string concatenation and conversion, see * <i>The Java Language Specification</i>. * * @version 12/17/01 (CLDC 1.1) * @see java.lang.Object#toString() * @see java.lang.StringBuffer * @see java.lang.StringBuffer#append(boolean) * @see java.lang.StringBuffer#append(char) * @see java.lang.StringBuffer#append(char[]) * @see java.lang.StringBuffer#append(char[], int, int) * @see java.lang.StringBuffer#append(int) * @see java.lang.StringBuffer#append(long) * @see java.lang.StringBuffer#append(java.lang.Object) * @see java.lang.StringBuffer#append(java.lang.String) * @since JDK1.0, CLDC 1.0 */ public final class String { /** The value is used for character storage. */ private char value[]; /** The offset is the first index of the storage that is used. */ private int offset; /** The count is the number of characters in the String. */ private int count; /** * Initializes a newly created <code>String</code> object so that it * represents an empty character sequence. */ public String() { value = new char[0]; } /** * Initializes a newly created <code>String</code> object so that it * represents the same sequence of characters as the argument; in other * words, the newly created string is a copy of the argument string. * * @param value a <code>String</code>. */ public String(String value) { count = value.length(); this.value = new char[count]; value.getChars(0, count, this.value, 0); } /** * Allocates a new <code>String</code> so that it represents the * sequence of characters currently contained in the character array * argument. The contents of the character array are copied; subsequent * modification of the character array does not affect the newly created * string. * * @param value the initial value of the string. * @throws NullPointerException if <code>value</code> is <code>null</code>. */ public String(char value[]) { this.count = value.length; this.value = new char[count]; JVM.unchecked_char_arraycopy(value, 0, this.value, 0, count); } /** * Allocates a new <code>String</code> that contains characters from * a subarray of the character array argument. The <code>offset</code> * argument is the index of the first character of the subarray and * the <code>count</code> argument specifies the length of the * subarray. The contents of the subarray are copied; subsequent * modification of the character array does not affect the newly * created string. * * @param value array that is the source of characters. * @param offset the initial offset. * @param count the length. * @exception IndexOutOfBoundsException if the <code>offset</code> * and <code>count</code> arguments index characters outside * the bounds of the <code>value</code> array. * @exception NullPointerException if <code>value</code> is * <code>null</code>. */ public String(char value[], int offset, int count) { if (offset < 0) { throw new StringIndexOutOfBoundsException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped offset /* #endif */ ); } if (count < 0) { throw new StringIndexOutOfBoundsException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped count /* #endif */ ); } // Note: offset or count might be near -1>>>1. if (offset > value.length - count) { throw new StringIndexOutOfBoundsException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped offset + count /* #endif */ ); } this.value = new char[count]; this.count = count; JVM.unchecked_char_arraycopy(value, offset, this.value, 0, count); } /** * Construct a new <code>String</code> by converting the specified * subarray of bytes using the specified character encoding. The length of * the new <code>String</code> is a function of the encoding, and hence may * not be equal to the length of the subarray. * * @param bytes The bytes to be converted into characters * @param off Index of the first byte to convert * @param len Number of bytes to convert * @param enc The name of a character encoding * * @exception UnsupportedEncodingException * If the named encoding is not supported * @since JDK1.1 */ public String(byte bytes[], int off, int len, String enc) throws UnsupportedEncodingException { this(Helper.byteToCharArray(bytes, off, len, enc)); } /** * Construct a new <code>String</code> by converting the specified array * of bytes using the specified character encoding. The length of the new * <code>String</code> is a function of the encoding, and hence may not be * equal to the length of the byte array. * * @param bytes The bytes to be converted into characters * @param enc The name of a supported character encoding * * @exception UnsupportedEncodingException * If the named encoding is not supported * @since JDK1.1 */ public String(byte bytes[], String enc) throws UnsupportedEncodingException { this(bytes, 0, bytes.length, enc); } /** * Construct a new <code>String</code> by converting the specified * subarray of bytes using the platform's default character encoding. The * length of the new <code>String</code> is a function of the encoding, and * hence may not be equal to the length of the subarray. * * @param bytes The bytes to be converted into characters * @param off Index of the first byte to convert * @param len Number of bytes to convert * @since JDK1.1 */ public String(byte bytes[], int off, int len) { this(Helper.byteToCharArray(bytes, off, len)); } /** * Construct a new <code>String</code> by converting the specified array * of bytes using the platform's default character encoding. The length of * the new <code>String</code> is a function of the encoding, and hence may * not be equal to the length of the byte array. * * @param bytes The bytes to be converted into characters * @since JDK1.1 */ public String(byte bytes[]) { this(bytes, 0, bytes.length); } /** * Allocates a new string that contains the sequence of characters * currently contained in the string buffer argument. The contents of * the string buffer are copied; subsequent modification of the string * buffer does not affect the newly created string. * * @param buffer a <code>StringBuffer</code>. * @throws NullPointerException If <code>buffer</code> is * <code>null</code>. */ public String (StringBuffer buffer) { synchronized(buffer) { buffer.setShared(); this.value = buffer.getValue(); this.offset = 0; this.count = buffer.length(); } } // Package private constructor which shares value array for speed. String(int offset, int count, char value[]) { this.value = value; this.offset = offset; this.count = count; } /** * Returns the length of this string. * The length is equal to the number of 16-bit * Unicode characters in the string. * * @return the length of the sequence of characters represented by this * object. */ public int length() { return count; } /** * Returns the character at the specified index. An index ranges * from <code>0</code> to <code>length() - 1</code>. The first character * of the sequence is at index <code>0</code>, the next at index * <code>1</code>, and so on, as for array indexing. * * @param index the index of the character. * @return the character at the specified index of this string. * The first character is at index <code>0</code>. * @exception IndexOutOfBoundsException if the <code>index</code> * argument is negative or not less than the length of this * string. */ public char charAt(int index) { if ((index < 0) || (index >= count)) { throw new StringIndexOutOfBoundsException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped index /* #endif */ ); } return value[index + offset]; } /** * Copies characters from this string into the destination character * array. * <p> * The first character to be copied is at index <code>srcBegin</code>; * the last character to be copied is at index <code>srcEnd-1</code> * (thus the total number of characters to be copied is * <code>srcEnd-srcBegin</code>). The characters are copied into the * subarray of <code>dst</code> starting at index <code>dstBegin</code> * and ending at index: * <p><blockquote><pre> * dstbegin + (srcEnd-srcBegin) - 1 * </pre></blockquote> * * @param srcBegin index of the first character in the string * to copy. * @param srcEnd index after the last character in the string * to copy. * @param dst the destination array. * @param dstBegin the start offset in the destination array. * @exception IndexOutOfBoundsException If any of the following * is true: * <ul><li><code>srcBegin</code> is negative. * <li><code>srcBegin</code> is greater than <code>srcEnd</code> * <li><code>srcEnd</code> is greater than the length of this * string * <li><code>dstBegin</code> is negative * <li><code>dstBegin+(srcEnd-srcBegin)</code> is larger than * <code>dst.length</code></ul> * @exception NullPointerException if <code>dst</code> is <code>null</code> */ public void getChars(int srcBegin, int srcEnd, char dst[], int dstBegin) { if (srcBegin < 0) { throw new StringIndexOutOfBoundsException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped srcBegin /* #endif */ ); } if (srcEnd > count) { throw new StringIndexOutOfBoundsException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped srcEnd /* #endif */ ); } if (srcBegin > srcEnd) { throw new StringIndexOutOfBoundsException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped srcEnd - srcBegin /* #endif */ ); } // NOTE: dst not checked, cannot use unchecked arraycopy System.arraycopy(value, offset + srcBegin, dst, dstBegin, srcEnd - srcBegin); } /** * Convert this <code>String</code> into bytes according to the specified * character encoding, storing the result into a new byte array. * * @param enc A character-encoding name * @return The resultant byte array * * @exception UnsupportedEncodingException * If the named encoding is not supported * @since JDK1.1 */ public byte[] getBytes(String enc) throws UnsupportedEncodingException { return Helper.charToByteArray(value, offset, count, enc); } /** * Convert this <code>String</code> into bytes according to the platform's * default character encoding, storing the result into a new byte array. * * @return the resultant byte array. * @since JDK1.1 */ public byte[] getBytes() { return Helper.charToByteArray(value, offset, count); } /** * Compares this string to the specified object. * The result is <code>true</code> if and only if the argument is not * <code>null</code> and is a <code>String</code> object that represents * the same sequence of characters as this object. * * @param anObject the object to compare this <code>String</code> * against. * @return <code>true</code> if the <code>String </code>are equal; * <code>false</code> otherwise. * @see java.lang.String#compareTo(java.lang.String) * @see java.lang.String#equalsIgnoreCase(java.lang.String) */ /* public native boolean equals(Object anObject); */ public boolean equals(Object anObject) { if (this == anObject) { return true; } if (anObject instanceof String) { String anotherString = (String)anObject; int n = count; if (n == anotherString.count) { char v1[] = value; char v2[] = anotherString.value; int i = offset; int j = anotherString.offset; while (n-- != 0) { if (v1[i++] != v2[j++]) { return false; } } return true; } } return false; } /** * Compares this <code>String</code> to another <code>String</code>, * ignoring case considerations. Two strings are considered equal * ignoring case if they are of the same length, and corresponding * characters in the two strings are equal ignoring case. * <p> * Two characters <code>c1</code> and <code>c2</code> are considered * the same, ignoring case if at least one of the following is true: * <ul><li>The two characters are the same (as compared by the * <code>==</code> operator). * <li>Applying the method {@link java.lang.Character#toUpperCase(char)} * to each character produces the same result. * <li>Applying the method {@link java.lang.Character#toLowerCase(char)} * to each character produces the same result.</ul> * * @param anotherString the <code>String</code> to compare this * <code>String</code> against. * @return <code>true</code> if the argument is not <code>null</code> * and the <code>String</code>s are equal, * ignoring case; <code>false</code> otherwise. * @see #equals(Object) * @see java.lang.Character#toLowerCase(char) * @see java.lang.Character#toUpperCase(char) */ public boolean equalsIgnoreCase(String anotherString) { return (anotherString != null) && (anotherString.count == count) && regionMatches(true, 0, anotherString, 0, count); } /** * Compares two strings lexicographically. * The comparison is based on the Unicode value of each character in * the strings. The character sequence represented by this * <code>String</code> object is compared lexicographically to the * character sequence represented by the argument string. The result is * a negative integer if this <code>String</code> object * lexicographically precedes the argument string. The result is a * positive integer if this <code>String</code> object lexicographically * follows the argument string. The result is zero if the strings * are equal; <code>compareTo</code> returns <code>0</code> exactly when * the {@link #equals(Object)} method would return <code>true</code>. * <p> * This is the definition of lexicographic ordering. If two strings are * different, then either they have different characters at some index * that is a valid index for both strings, or their lengths are different, * or both. If they have different characters at one or more index * positions, let <i>k</i> be the smallest such index; then the string * whose character at position <i>k</i> has the smaller value, as * determined by using the < operator, lexicographically precedes the * other string. In this case, <code>compareTo</code> returns the * difference of the two character values at position <i>k</i> in * the two string -- that is, the value: * <blockquote><pre> * this.charAt(k)-anotherString.charAt(k) * </pre></blockquote> * If there is no index position at which they differ, then the shorter * string lexicographically precedes the longer string. In this case, * <code>compareTo</code> returns the difference of the lengths of the * strings -- that is, the value: * <blockquote><pre> * this.length()-anotherString.length() * </pre></blockquote> * * @param anotherString the <code>String</code> to be compared. * @return the value <code>0</code> if the argument string is equal to * this string; a value less than <code>0</code> if this string * is lexicographically less than the string argument; and a * value greater than <code>0</code> if this string is * lexicographically greater than the string argument. * @exception java.lang.NullPointerException if <code>anotherString</code> * is <code>null</code>. */ public int compareTo(String anotherString) { int len1 = count; int len2 = anotherString.count; int n = Math.min(len1, len2); char v1[] = value; char v2[] = anotherString.value; int i = offset; int j = anotherString.offset; if (i == j) { int k = i; int lim = n + i; while (k < lim) { char c1 = v1[k]; char c2 = v2[k]; if (c1 != c2) { return c1 - c2; } k++; } } else { while (n-- != 0) { char c1 = v1[i++]; char c2 = v2[j++]; if (c1 != c2) { return c1 - c2; } } } return len1 - len2; } /** * Tests if two string regions are equal. * <p> * A substring of this <tt>String</tt> object is compared to a substring * of the argument <tt>other</tt>. The result is <tt>true</tt> if these * substrings represent character sequences that are the same, ignoring * case if and only if <tt>ignoreCase</tt> is true. The substring of * this <tt>String</tt> object to be compared begins at index * <tt>toffset</tt> and has length <tt>len</tt>. The substring of * <tt>other</tt> to be compared begins at index <tt>ooffset</tt> and * has length <tt>len</tt>. The result is <tt>false</tt> if and only if * at least one of the following is true: * <ul><li><tt>toffset</tt> is negative. * <li><tt>ooffset</tt> is negative. * <li><tt>toffset+len</tt> is greater than the length of this * <tt>String</tt> object. * <li><tt>ooffset+len</tt> is greater than the length of the other * argument. * <li>There is some nonnegative integer <i>k</i> less than <tt>len</tt> * such that: * <blockquote><pre> * this.charAt(toffset+k) != other.charAt(ooffset+k) * </pre></blockquote> * <li><tt>ignoreCase</tt> is <tt>true</tt> and there is some nonnegative * integer <i>k</i> less than <tt>len</tt> such that: * <blockquote><pre> * Character.toLowerCase(this.charAt(toffset+k)) != Character.toLowerCase(other.charAt(ooffset+k)) * </pre></blockquote> * and: * <blockquote><pre> * Character.toUpperCase(this.charAt(toffset+k)) != * Character.toUpperCase(other.charAt(ooffset+k)) * </pre></blockquote> * </ul> * * @param ignoreCase if <code>true</code>, ignore case when comparing * characters. * @param toffset the starting offset of the subregion in this * string. * @param other the string argument. * @param ooffset the starting offset of the subregion in the string * argument. * @param len the number of characters to compare. * @return <code>true</code> if the specified subregion of this string * matches the specified subregion of the string argument; * <code>false</code> otherwise. Whether the matching is exact * or case insensitive depends on the <code>ignoreCase</code> * argument. */ public boolean regionMatches(boolean ignoreCase, int toffset, String other, int ooffset, int len) { char ta[] = value; int to = offset + toffset; int tlim = offset + count; char pa[] = other.value; int po = other.offset + ooffset; // Note: toffset, ooffset, or len might be near -1>>>1. if ((ooffset < 0) || (toffset < 0) || (toffset > (long)count - len) || (ooffset > (long)other.count - len)) { return false; } while (len-- > 0) { char c1 = ta[to++]; char c2 = pa[po++]; if (c1 == c2) continue; if (ignoreCase) { // If characters don't match but case may be ignored, // try converting both characters to uppercase. // If the results match, then the comparison scan should // continue. char u1 = Character.toUpperCase(c1); char u2 = Character.toUpperCase(c2); if (u1 == u2) continue; // Unfortunately, conversion to uppercase does not work properly // for the Georgian alphabet, which has strange rules about case // conversion. So we need to make one last check before // exiting. if (Character.toLowerCase(u1) == Character.toLowerCase(u2)) continue; } return false; } return true; } /** * Tests if this string starts with the specified prefix beginning * at the specified index. * * @param prefix the prefix. * @param toffset where to begin looking in the string. * @return <code>true</code> if the character sequence represented by the * argument is a prefix of the substring of this object starting * at index <code>toffset</code>; <code>false</code> otherwise. * The result is <code>false</code> if <code>toffset</code> is * negative or greater than the length of this * <code>String</code> object; otherwise the result is the same * as the result of the expression * <pre> * this.subString(toffset).startsWith(prefix) * </pre> * @exception java.lang.NullPointerException if <code>prefix</code> is * <code>null</code>. */ public boolean startsWith(String prefix, int toffset) { char ta[] = value; int to = offset + toffset; int tlim = offset + count; char pa[] = prefix.value; int po = prefix.offset; int pc = prefix.count; // Note: toffset might be near -1>>>1. if ((toffset < 0) || (toffset > count - pc)) { return false; } while (--pc >= 0) { if (ta[to++] != pa[po++]) { return false; } } return true; } /** * Tests if this string starts with the specified prefix. * * @param prefix the prefix. * @return <code>true</code> if the character sequence represented by the * argument is a prefix of the character sequence represented by * this string; <code>false</code> otherwise. * Note also that <code>true</code> will be returned if the * argument is an empty string or is equal to this * <code>String</code> object as determined by the * {@link #equals(Object)} method. * @exception java.lang.NullPointerException if <code>prefix</code> is * <code>null</code>. * @since JDK1.0 */ public boolean startsWith(String prefix) { return startsWith(prefix, 0); } /** * Tests if this string ends with the specified suffix. * * @param suffix the suffix. * @return <code>true</code> if the character sequence represented by the * argument is a suffix of the character sequence represented by * this object; <code>false</code> otherwise. Note that the * result will be <code>true</code> if the argument is the * empty string or is equal to this <code>String</code> object * as determined by the {@link #equals(Object)} method. * @exception java.lang.NullPointerException if <code>suffix</code> is * <code>null</code>. */ public boolean endsWith(String suffix) { return startsWith(suffix, count - suffix.count); } /** * Returns a hashcode for this string. The hashcode for a * <code>String</code> object is computed as * <blockquote><pre> * s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1] * </pre></blockquote> * using <code>int</code> arithmetic, where <code>s[i]</code> is the * <i>i</i>th character of the string, <code>n</code> is the length of * the string, and <code>^</code> indicates exponentiation. * (The hash value of the empty string is zero.) * * @return a hash code value for this object. */ public native int hashCode(); /* public int hashCode() { int h = 0; int off = offset; char val[] = value; int len = count; for (int i = 0; i < len; i++) { h = 31*h + val[off++]; } return h; } */ /** * Returns the index within this string of the first occurrence of the * specified character. If a character with value <code>ch</code> occurs * in the character sequence represented by this <code>String</code> * object, then the index of the first such occurrence is returned -- * that is, the smallest value <i>k</i> such that: * <blockquote><pre> * this.charAt(<i>k</i>) == ch * </pre></blockquote> * is <code>true</code>. If no such character occurs in this string, * then <code>-1</code> is returned. * * @param ch a character. * @return the index of the first occurrence of the character in the * character sequence represented by this object, or * <code>-1</code> if the character does not occur. */ public native int indexOf(int ch); /* public int indexOf(int ch) { return indexOf(ch, 0); } */ /** * Returns the index within this string of the first occurrence of the * specified character, starting the search at the specified index. * <p> * If a character with value <code>ch</code> occurs in the character * sequence represented by this <code>String</code> object at an index * no smaller than <code>fromIndex</code>, then the index of the first * such occurrence is returned--that is, the smallest value <i>k</i> * such that: * <blockquote><pre> * (this.charAt(<i>k</i>) == ch) && (<i>k</i> >= fromIndex) * </pre></blockquote> * is true. If no such character occurs in this string at or after * position <code>fromIndex</code>, then <code>-1</code> is returned. * <p> * There is no restriction on the value of <code>fromIndex</code>. If it * is negative, it has the same effect as if it were zero: this entire * string may be searched. If it is greater than the length of this * string, it has the same effect as if it were equal to the length of * this string: <code>-1</code> is returned. * * @param ch a character. * @param fromIndex the index to start the search from. * @return the index of the first occurrence of the character in the * character sequence represented by this object that is greater * than or equal to <code>fromIndex</code>, or <code>-1</code> * if the character does not occur. */ public native int indexOf(int ch, int fromIndex); /************ * public int indexOf(int ch, int fromIndex) { * int max = offset + count; * char v[] = value; * * if (fromIndex < 0) { * fromIndex = 0; * } else if (fromIndex >= count) { * // Note: fromIndex might be near -1>>>1. * return -1; * } * for (int i = offset + fromIndex ; i < max ; i++) { * if (v[i] == ch) { * return i - offset; * } * } * return -1; * } ******/ /** * Returns the index within this string of the last occurrence of the * specified character. That is, the index returned is the largest * value <i>k</i> such that: * <blockquote><pre> * this.charAt(<i>k</i>) == ch * </pre></blockquote> * is true. * The String is searched backwards starting at the last character. * * @param ch a character. * @return the index of the last occurrence of the character in the * character sequence represented by this object, or * <code>-1</code> if the character does not occur. */ public native int lastIndexOf(int ch); /* public int lastIndexOf(int ch) { return lastIndexOf(ch, count - 1); } */ /** * Returns the index within this string of the last occurrence of the * specified character, searching backward starting at the specified * index. That is, the index returned is the largest value <i>k</i> * such that: * <blockquote><pre> * (this.charAt(k) == ch) && (k <= fromIndex) * </pre></blockquote> * is true. * * @param ch a character. * @param fromIndex the index to start the search from. There is no * restriction on the value of <code>fromIndex</code>. If it is * greater than or equal to the length of this string, it has * the same effect as if it were equal to one less than the * length of this string: this entire string may be searched. * If it is negative, it has the same effect as if it were -1: * -1 is returned. * @return the index of the last occurrence of the character in the * character sequence represented by this object that is less * than or equal to <code>fromIndex</code>, or <code>-1</code> * if the character does not occur before that point. */ public native int lastIndexOf(int ch, int fromIndex); /* public int lastIndexOf(int ch, int fromIndex) { int min = offset; char v[] = value; for (int i = offset + ((fromIndex >= count) ? count - 1 : fromIndex) ; i >= min ; i--) { if (v[i] == ch) { return i - offset; } } return -1; } */ /** * Returns the index within this string of the first occurrence of the * specified substring. The integer returned is the smallest value * <i>k</i> such that: * <blockquote><pre> * this.startsWith(str, <i>k</i>) * </pre></blockquote> * is <code>true</code>. * * @param str any string. * @return if the string argument occurs as a substring within this * object, then the index of the first character of the first * such substring is returned; if it does not occur as a * substring, <code>-1</code> is returned. * @exception java.lang.NullPointerException if <code>str</code> is * <code>null</code>. */ public int indexOf(String str) { return indexOf(str, 0); } /** * Returns the index within this string of the first occurrence of the * specified substring, starting at the specified index. The integer * returned is the smallest value <i>k</i> such that: * <blockquote><pre> * this.startsWith(str, <i>k</i>) && (<i>k</i> >= fromIndex) * </pre></blockquote> * is <code>true</code>. * <p> * There is no restriction on the value of <code>fromIndex</code>. If * it is negative, it has the same effect as if it were zero: this entire * string may be searched. If it is greater than the length of this * string, it has the same effect as if it were equal to the length of * this string: <code>-1</code> is returned. * * @param str the substring to search for. * @param fromIndex the index to start the search from. * @return If the string argument occurs as a substring within this * object at a starting index no smaller than * <code>fromIndex</code>, then the index of the first character * of the first such substring is returned. If it does not occur * as a substring starting at <code>fromIndex</code> or beyond, * <code>-1</code> is returned. * @exception java.lang.NullPointerException if <code>str</code> is * <code>null</code> */ public int indexOf(String str, int fromIndex) { char v1[] = value; char v2[] = str.value; int max = offset + (count - str.count); if (fromIndex >= count) { if (count == 0 && fromIndex == 0 && str.count == 0) { /* There is an empty string at index 0 in an empty string. */ return 0; } /* Note: fromIndex might be near -1>>>1 */ return -1; } if (fromIndex < 0) { fromIndex = 0; } if (str.count == 0) { return fromIndex; } int strOffset = str.offset; char first = v2[strOffset]; int i = offset + fromIndex; startSearchForFirstChar: while (true) { /* Look for first character. */ while (i <= max && v1[i] != first) { i++; } if (i > max) { return -1; } /* Found first character, now look at the rest of v2 */ int j = i + 1; int end = j + str.count - 1; int k = strOffset + 1; while (j < end) { if (v1[j++] != v2[k++]) { i++; /* Look for str's first char again. */ continue startSearchForFirstChar; } } return i - offset; /* Found whole string. */ } } /** * Returns a new string that is a substring of this string. The * substring begins with the character at the specified index and * extends to the end of this string. <p> * Examples: * <blockquote><pre> * "unhappy".substring(2) returns "happy" * "Harbison".substring(3) returns "bison" * "emptiness".substring(9) returns "" (an empty string) * </pre></blockquote> * * @param beginIndex the beginning index, inclusive. * @return the specified substring. * @exception IndexOutOfBoundsException if * <code>beginIndex</code> is negative or larger than the * length of this <code>String</code> object. */ public String substring(int beginIndex) { return substring(beginIndex, count); } /** * Returns a new string that is a substring of this string. The * substring begins at the specified <code>beginIndex</code> and * extends to the character at index <code>endIndex - 1</code>. * Thus the length of the substring is <code>endIndex-beginIndex</code>. * <p> * Examples: * <blockquote><pre> * "hamburger".substring(4, 8) returns "urge" * "smiles".substring(1, 5) returns "mile" * </pre></blockquote> * * @param beginIndex the beginning index, inclusive. * @param endIndex the ending index, exclusive. * @return the specified substring. * @exception IndexOutOfBoundsException if the * <code>beginIndex</code> is negative, or * <code>endIndex</code> is larger than the length of * this <code>String</code> object, or * <code>beginIndex</code> is larger than * <code>endIndex</code>. */ public String substring(int beginIndex, int endIndex) { if (beginIndex < 0) { throw new StringIndexOutOfBoundsException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped beginIndex /* #endif */ ); } if (endIndex > count) { throw new StringIndexOutOfBoundsException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped endIndex /* #endif */ ); } if (beginIndex > endIndex) { throw new StringIndexOutOfBoundsException( /* #ifdef VERBOSE_EXCEPTIONS */ /// skipped endIndex - beginIndex /* #endif */ ); } return ((beginIndex == 0) && (endIndex == count)) ? this : new String(offset + beginIndex, endIndex - beginIndex, value); } /** * Concatenates the specified string to the end of this string. * <p> * If the length of the argument string is <code>0</code>, then this * <code>String</code> object is returned. Otherwise, a new * <code>String</code> object is created, representing a character * sequence that is the concatenation of the character sequence * represented by this <code>String</code> object and the character * sequence represented by the argument string.<p> * Examples: * <blockquote><pre> * "cares".concat("s") returns "caress" * "to".concat("get").concat("her") returns "together" * </pre></blockquote> * * @param str the <code>String</code> that is concatenated to the end * of this <code>String</code>. * @return a string that represents the concatenation of this object's * characters followed by the string argument's characters. * @exception java.lang.NullPointerException if <code>str</code> is * <code>null</code>. */ public String concat(String str) { int otherLen = str.length(); if (otherLen == 0) { return this; } char buf[] = new char[count + otherLen]; getChars(0, count, buf, 0); str.getChars(0, otherLen, buf, count); return new String(0, count + otherLen, buf); } /** * Returns a new string resulting from replacing all occurrences of * <code>oldChar</code> in this string with <code>newChar</code>. * <p> * If the character <code>oldChar</code> does not occur in the * character sequence represented by this <code>String</code> object, * then a reference to this <code>String</code> object is returned. * Otherwise, a new <code>String</code> object is created that * represents a character sequence identical to the character sequence * represented by this <code>String</code> object, except that every * occurrence of <code>oldChar</code> is replaced by an occurrence * of <code>newChar</code>. * <p> * Examples: * <blockquote><pre> * "mesquite in your cellar".replace('e', 'o') * returns "mosquito in your collar" * "the war of baronets".replace('r', 'y') * returns "the way of bayonets" * "sparring with a purple porpoise".replace('p', 't') * returns "starring with a turtle tortoise" * "JonL".replace('q', 'x') returns "JonL" (no change) * </pre></blockquote> * * @param oldChar the old character. * @param newChar the new character. * @return a string derived from this string by replacing every * occurrence of <code>oldChar</code> with <code>newChar</code>. */ public String replace(char oldChar, char newChar) { if (oldChar != newChar) { int len = count; int i = -1; char[] val = value; /* avoid getfield opcode */ int off = offset; /* avoid getfield opcode */ while (++i < len) { if (val[off + i] == oldChar) { break; } } if (i < len) { char buf[] = new char[len]; for (int j = 0 ; j < i ; j++) { buf[j] = val[off+j]; } while (i < len) { char c = val[off + i]; buf[i] = (c == oldChar) ? newChar : c; i++; } return new String(0, len, buf); } } return this; } /** * Converts all of the characters in this <code>String</code> to lower case. * * @return the String, converted to lowercase. * @see Character#toLowerCase * @see String#toUpperCase */ public String toLowerCase() { int i; scan : { for(i = 0 ; i < count ; i++) { char c = value[offset+i]; if (c != Character.toLowerCase(c)) { break scan; } } return this; } char buf[] = new char[count]; JVM.unchecked_char_arraycopy(value, offset, buf, 0, i); for(; i < count ; i++) { buf[i] = Character.toLowerCase(value[offset+i]); } return new String(0, count, buf); } /** * Converts all of the characters in this <code>String</code> to upper case. * * @return the String, converted to uppercase. * @see Character#toLowerCase * @see String#toUpperCase */ public String toUpperCase() { int i; scan : { for(i = 0 ; i < count ; i++) { char c = value[offset+i]; if (c != Character.toUpperCase(c)) { break scan; } } return this; } char buf[] = new char[count]; JVM.unchecked_char_arraycopy(value, offset, buf, 0, i); for(; i < count ; i++) { buf[i] = Character.toUpperCase(value[offset+i]); } return new String(0, count, buf); } /** * Removes white space from both ends of this string. * <p> * If this <code>String</code> object represents an empty character * sequence, or the first and last characters of character sequence * represented by this <code>String</code> object both have codes * greater than <code>'\u0020'</code> (the space character), then a * reference to this <code>String</code> object is returned. * <p> * Otherwise, if there is no character with a code greater than * <code>'\u0020'</code> in the string, then a new * <code>String</code> object representing an empty string is created * and returned. * <p> * Otherwise, let <i>k</i> be the index of the first character in the * string whose code is greater than <code>'\u0020'</code>, and let * <i>m</i> be the index of the last character in the string whose code * is greater than <code>'\u0020'</code>. A new <code>String</code> * object is created, representing the substring of this string that * begins with the character at index <i>k</i> and ends with the * character at index <i>m</i>-that is, the result of * <code>this.substring(<i>k</i>, <i>m</i>+1)</code>. * <p> * This method may be used to trim whitespace from the beginning and end * of a string; in fact, it trims all ASCII control characters as well. * * @return this string, with white space removed from the front and end. */ public String trim() { int len = count; int st = 0; int off = offset; /* avoid getfield opcode */ char[] val = value; /* avoid getfield opcode */ while ((st < len) && (val[off + st] <= ' ')) { st++; } while ((st < len) && (val[off + len - 1] <= ' ')) { len--; } return ((st > 0) || (len < count)) ? substring(st, len) : this; } /** * This object (which is already a string!) is itself returned. * * @return the string itself. */ public String toString() { return this; } /** * Converts this string to a new character array. * * @return a newly allocated character array whose length is the length * of this string and whose contents are initialized to contain * the character sequence represented by this string. */ public char[] toCharArray() { char result[] = new char[count]; getChars(0, count, result, 0); return result; } /** * Returns the string representation of the <code>Object</code> argument. * * @param obj an <code>Object</code>. * @return if the argument is <code>null</code>, then a string equal to * <code>"null"</code>; otherwise, the value of * <code>obj.toString()</code> is returned. * @see java.lang.Object#toString() */ public static String valueOf(Object obj) { return (obj == null) ? "null" : obj.toString(); } /** * Returns the string representation of the <code>char</code> array * argument. The contents of the character array are copied; subsequent * modification of the character array does not affect the newly * created string. * * @param data a <code>char</code> array. * @return a newly allocated string representing the same sequence of * characters contained in the character array argument. */ public static String valueOf(char data[]) { return new String(data); } /** * Returns the string representation of a specific subarray of the * <code>char</code> array argument. * <p> * The <code>offset</code> argument is the index of the first * character of the subarray. The <code>count</code> argument * specifies the length of the subarray. The contents of the subarray * are copied; subsequent modification of the character array does not * affect the newly created string. * * @param data the character array. * @param offset the initial offset into the value of the * <code>String</code>. * @param count the length of the value of the <code>String</code>. * @return a newly allocated string representing the sequence of * characters contained in the subarray of the character array * argument. * @exception NullPointerException if <code>data</code> is * <code>null</code>. * @exception IndexOutOfBoundsException if <code>offset</code> is * negative, or <code>count</code> is negative, or * <code>offset+count</code> is larger than * <code>data.length</code>. */ public static String valueOf(char data[], int offset, int count) { return new String(data, offset, count); } /** * Returns the string representation of the <code>boolean</code> argument. * * @param b a <code>boolean</code>. * @return if the argument is <code>true</code>, a string equal to * <code>"true"</code> is returned; otherwise, a string equal to * <code>"false"</code> is returned. */ public static String valueOf(boolean b) { return b ? "true" : "false"; } /** * Returns the string representation of the <code>char</code> * argument. * * @param c a <code>char</code>. * @return a newly allocated string of length <code>1</code> containing * as its single character the argument <code>c</code>. */ public static String valueOf(char c) { char data[] = {c}; return new String(0, 1, data); } /** * Returns the string representation of the <code>int</code> argument. * <p> * The representation is exactly the one returned by the * <code>Integer.toString</code> method of one argument. * * @param i an <code>int</code>. * @return a newly allocated string containing a string representation of * the <code>int</code> argument. * @see java.lang.Integer#toString(int, int) */ public static String valueOf(int i) { return Integer.toString(i, 10); } /** * Returns the string representation of the <code>long</code> argument. * <p> * The representation is exactly the one returned by the * <code>Long.toString</code> method of one argument. * * @param l a <code>long</code>. * @return a newly allocated string containing a string representation of * the <code>long</code> argument. * @see java.lang.Long#toString(long) */ public static String valueOf(long l) { return Long.toString(l, 10); } /** * Returns the string representation of the <code>float</code> argument. * <p> * The representation is exactly the one returned by the * <code>Float.toString</code> method of one argument. * * @param f a <code>float</code>. * @return a newly allocated string containing a string representation of * the <code>float</code> argument. * @see java.lang.Float#toString(float) * @since CLDC 1.1 */ public static String valueOf(float f) { return Float.toString(f); } /** * Returns the string representation of the <code>double</code> argument. * <p> * The representation is exactly the one returned by the * <code>Double.toString</code> method of one argument. * * @param d a <code>double</code>. * @return a newly allocated string containing a string representation of * the <code>double</code> argument. * @see java.lang.Double#toString(double) * @since CLDC 1.1 */ public static String valueOf(double d) { return Double.toString(d); } /** * Returns a canonical representation for the string object. * <p> * A pool of strings, initially empty, is maintained privately by the * class <code>String</code>. * <p> * When the intern method is invoked, if the pool already contains a * string equal to this <code>String</code> object as determined by * the {@link #equals(Object)} method, then the string from the pool is * returned. Otherwise, this <code>String</code> object is added to the * pool and a reference to this <code>String</code> object is returned. * <p> * It follows that for any two strings <code>s</code> and <code>t</code>, * <code>s.intern() == t.intern()</code> is <code>true</code> * if and only if <code>s.equals(t)</code> is <code>true</code>. * <p> * All literal strings and string-valued constant expressions are * interned. String literals are defined in Section 3.10.5 of the * <a href="http://java.sun.com/docs/books/jls/html/">Java Language * Specification</a> * * @return a string that has the same contents as this string, but is * guaranteed to be from a pool of unique strings. * @since CLDC 1.1 */ public native String intern(); }