| /* StringBuilder.java -- Unsynchronized growable strings |
| Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2008 |
| Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package java.lang; |
| |
| import java.io.Serializable; |
| |
| /** |
| * <code>StringBuilder</code> represents a changeable <code>String</code>. |
| * It provides the operations required to modify the |
| * <code>StringBuilder</code>, including insert, replace, delete, append, |
| * and reverse. It like <code>StringBuffer</code>, but is not |
| * synchronized. It is ideal for use when it is known that the |
| * object will only be used from a single thread. |
| * |
| * <p><code>StringBuilder</code>s are variable-length in nature, so even if |
| * you initialize them to a certain size, they can still grow larger than |
| * that. <em>Capacity</em> indicates the number of characters the |
| * <code>StringBuilder</code> can have in it before it has to grow (growing |
| * the char array is an expensive operation involving <code>new</code>). |
| * |
| * <p>Incidentally, compilers often implement the String operator "+" |
| * by using a <code>StringBuilder</code> operation:<br> |
| * <code>a + b</code><br> |
| * is the same as<br> |
| * <code>new StringBuilder().append(a).append(b).toString()</code>. |
| * |
| * <p>Classpath's StringBuilder is capable of sharing memory with Strings for |
| * efficiency. This will help when a StringBuilder is converted to a String |
| * and the StringBuilder is not changed after that (quite common when |
| * performing string concatenation). |
| * |
| * @author Paul Fisher |
| * @author John Keiser |
| * @author Tom Tromey |
| * @author Eric Blake (ebb9@email.byu.edu) |
| * @see String |
| * @see StringBuffer |
| * |
| * @since 1.5 |
| */ |
| public final class StringBuilder |
| extends AbstractStringBuffer |
| implements Serializable, CharSequence, Appendable |
| { |
| // Implementation note: if you change this class, you usually will |
| // want to change StringBuffer as well. |
| |
| /** |
| * For compatability with Sun's JDK |
| */ |
| private static final long serialVersionUID = 4383685877147921099L; |
| |
| /** |
| * Create a new StringBuilder with default capacity 16. |
| */ |
| public StringBuilder() |
| { |
| super(); |
| } |
| |
| /** |
| * Create an empty <code>StringBuilder</code> with the specified initial |
| * capacity. |
| * |
| * @param capacity the initial capacity |
| * @throws NegativeArraySizeException if capacity is negative |
| */ |
| public StringBuilder(int capacity) |
| { |
| super(capacity); |
| } |
| |
| /** |
| * Create a new <code>StringBuilder</code> with the characters in the |
| * specified <code>String</code>. Initial capacity will be the size of the |
| * String plus 16. |
| * |
| * @param str the <code>String</code> to convert |
| * @throws NullPointerException if str is null |
| */ |
| public StringBuilder(String str) |
| { |
| super(str); |
| } |
| |
| /** |
| * Create a new <code>StringBuilder</code> with the characters in the |
| * specified <code>CharSequence</code>. Initial capacity will be the |
| * length of the sequence plus 16; if the sequence reports a length |
| * less than or equal to 0, then the initial capacity will be 16. |
| * |
| * @param seq the initializing <code>CharSequence</code> |
| * @throws NullPointerException if str is null |
| */ |
| public StringBuilder(CharSequence seq) |
| { |
| super(seq); |
| } |
| |
| /** |
| * Get the length of the <code>String</code> this <code>StringBuilder</code> |
| * would create. Not to be confused with the <em>capacity</em> of the |
| * <code>StringBuilder</code>. |
| * |
| * @return the length of this <code>StringBuilder</code> |
| * @see #capacity() |
| * @see #setLength(int) |
| */ |
| public int length() |
| { |
| return count; |
| } |
| |
| /** |
| * Get the total number of characters this <code>StringBuilder</code> can |
| * support before it must be grown. Not to be confused with <em>length</em>. |
| * |
| * @return the capacity of this <code>StringBuilder</code> |
| * @see #length() |
| * @see #ensureCapacity(int) |
| */ |
| public int capacity() |
| { |
| return value.length; |
| } |
| |
| /** |
| * Append the <code>String</code> value of the argument to this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param obj the <code>Object</code> to convert and append |
| * @return this <code>StringBuilder</code> |
| * @see String#valueOf(Object) |
| * @see #append(String) |
| */ |
| public StringBuilder append(Object obj) |
| { |
| super.append(obj); |
| return this; |
| } |
| |
| /** |
| * Append the <code>String</code> to this <code>StringBuilder</code>. If |
| * str is null, the String "null" is appended. |
| * |
| * @param str the <code>String</code> to append |
| * @return this <code>StringBuilder</code> |
| */ |
| public StringBuilder append(String str) |
| { |
| super.append(str); |
| return this; |
| } |
| |
| /** |
| * Append the <code>StringBuilder</code> value of the argument to this |
| * <code>StringBuilder</code>. This behaves the same as |
| * <code>append((Object) stringBuffer)</code>, except it is more efficient. |
| * |
| * @param stringBuffer the <code>StringBuilder</code> to convert and append |
| * @return this <code>StringBuilder</code> |
| * @see #append(Object) |
| */ |
| public StringBuilder append(StringBuffer stringBuffer) |
| { |
| super.append(stringBuffer); |
| return this; |
| } |
| |
| /** |
| * Append the <code>char</code> array to this <code>StringBuilder</code>. |
| * This is similar (but more efficient) than |
| * <code>append(new String(data))</code>, except in the case of null. |
| * |
| * @param data the <code>char[]</code> to append |
| * @return this <code>StringBuilder</code> |
| * @throws NullPointerException if <code>str</code> is <code>null</code> |
| * @see #append(char[], int, int) |
| */ |
| public StringBuilder append(char[] data) |
| { |
| super.append(data, 0, data.length); |
| return this; |
| } |
| |
| /** |
| * Append part of the <code>char</code> array to this |
| * <code>StringBuilder</code>. This is similar (but more efficient) than |
| * <code>append(new String(data, offset, count))</code>, except in the case |
| * of null. |
| * |
| * @param data the <code>char[]</code> to append |
| * @param offset the start location in <code>str</code> |
| * @param count the number of characters to get from <code>str</code> |
| * @return this <code>StringBuilder</code> |
| * @throws NullPointerException if <code>str</code> is <code>null</code> |
| * @throws IndexOutOfBoundsException if offset or count is out of range |
| * (while unspecified, this is a StringIndexOutOfBoundsException) |
| */ |
| public StringBuilder append(char[] data, int offset, int count) |
| { |
| super.append(data, offset, count); |
| return this; |
| } |
| |
| /** |
| * Append the <code>String</code> value of the argument to this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param bool the <code>boolean</code> to convert and append |
| * @return this <code>StringBuilder</code> |
| * @see String#valueOf(boolean) |
| */ |
| public StringBuilder append(boolean bool) |
| { |
| super.append(bool); |
| return this; |
| } |
| |
| /** |
| * Append the <code>char</code> to this <code>StringBuilder</code>. |
| * |
| * @param ch the <code>char</code> to append |
| * @return this <code>StringBuilder</code> |
| */ |
| public StringBuilder append(char ch) |
| { |
| super.append(ch); |
| return this; |
| } |
| |
| /** |
| * Append the characters in the <code>CharSequence</code> to this |
| * buffer. |
| * |
| * @param seq the <code>CharSequence</code> providing the characters |
| * @return this <code>StringBuilder</code> |
| */ |
| public StringBuilder append(CharSequence seq) |
| { |
| super.append(seq, 0, seq.length()); |
| return this; |
| } |
| |
| /** |
| * Append some characters from the <code>CharSequence</code> to this |
| * buffer. If the argument is null, the four characters "null" are |
| * appended. |
| * |
| * @param seq the <code>CharSequence</code> providing the characters |
| * @param start the starting index |
| * @param end one past the final index |
| * @return this <code>StringBuilder</code> |
| */ |
| public StringBuilder append(CharSequence seq, int start, |
| int end) |
| { |
| super.append(seq, start, end); |
| return this; |
| } |
| |
| /** |
| * Append the <code>String</code> value of the argument to this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param inum the <code>int</code> to convert and append |
| * @return this <code>StringBuilder</code> |
| * @see String#valueOf(int) |
| */ |
| // This is native in libgcj, for efficiency. |
| public StringBuilder append(int inum) |
| { |
| super.append(inum); |
| return this; |
| } |
| |
| /** |
| * Append the <code>String</code> value of the argument to this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param lnum the <code>long</code> to convert and append |
| * @return this <code>StringBuilder</code> |
| * @see String#valueOf(long) |
| */ |
| public StringBuilder append(long lnum) |
| { |
| super.append(lnum); |
| return this; |
| } |
| |
| /** |
| * Append the <code>String</code> value of the argument to this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param fnum the <code>float</code> to convert and append |
| * @return this <code>StringBuilder</code> |
| * @see String#valueOf(float) |
| */ |
| public StringBuilder append(float fnum) |
| { |
| super.append(fnum); |
| return this; |
| } |
| |
| /** |
| * Append the <code>String</code> value of the argument to this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param dnum the <code>double</code> to convert and append |
| * @return this <code>StringBuilder</code> |
| * @see String#valueOf(double) |
| */ |
| public StringBuilder append(double dnum) |
| { |
| super.append(dnum); |
| return this; |
| } |
| |
| /** |
| * Append the code point to this <code>StringBuilder</code>. |
| * This is like #append(char), but will append two characters |
| * if a supplementary code point is given. |
| * |
| * @param code the code point to append |
| * @return this <code>StringBuilder</code> |
| * @see Character#toChars(int, char[], int) |
| * @since 1.5 |
| */ |
| public StringBuilder appendCodePoint(int code) |
| { |
| super.appendCodePoint(code); |
| return this; |
| } |
| |
| /** |
| * Delete characters from this <code>StringBuilder</code>. |
| * <code>delete(10, 12)</code> will delete 10 and 11, but not 12. It is |
| * harmless for end to be larger than length(). |
| * |
| * @param start the first character to delete |
| * @param end the index after the last character to delete |
| * @return this <code>StringBuilder</code> |
| * @throws StringIndexOutOfBoundsException if start or end are out of bounds |
| */ |
| public StringBuilder delete(int start, int end) |
| { |
| super.delete(start, end); |
| return this; |
| } |
| |
| /** |
| * Delete a character from this <code>StringBuilder</code>. |
| * |
| * @param index the index of the character to delete |
| * @return this <code>StringBuilder</code> |
| * @throws StringIndexOutOfBoundsException if index is out of bounds |
| */ |
| public StringBuilder deleteCharAt(int index) |
| { |
| super.deleteCharAt(index); |
| return this; |
| } |
| |
| /** |
| * Replace characters between index <code>start</code> (inclusive) and |
| * <code>end</code> (exclusive) with <code>str</code>. If <code>end</code> |
| * is larger than the size of this StringBuilder, all characters after |
| * <code>start</code> are replaced. |
| * |
| * @param start the beginning index of characters to delete (inclusive) |
| * @param end the ending index of characters to delete (exclusive) |
| * @param str the new <code>String</code> to insert |
| * @return this <code>StringBuilder</code> |
| * @throws StringIndexOutOfBoundsException if start or end are out of bounds |
| * @throws NullPointerException if str is null |
| */ |
| public StringBuilder replace(int start, int end, String str) |
| { |
| super.replace(start, end, str); |
| return this; |
| } |
| |
| /** |
| * Creates a substring of this StringBuilder, starting at a specified index |
| * and ending at the end of this StringBuilder. |
| * |
| * @param beginIndex index to start substring (base 0) |
| * @return new String which is a substring of this StringBuilder |
| * @throws StringIndexOutOfBoundsException if beginIndex is out of bounds |
| * @see #substring(int, int) |
| */ |
| public String substring(int beginIndex) |
| { |
| return substring(beginIndex, count); |
| } |
| |
| /** |
| * Creates a substring of this StringBuilder, starting at a specified index |
| * and ending at one character before a specified index. This is implemented |
| * the same as <code>substring(beginIndex, endIndex)</code>, to satisfy |
| * the CharSequence interface. |
| * |
| * @param beginIndex index to start at (inclusive, base 0) |
| * @param endIndex index to end at (exclusive) |
| * @return new String which is a substring of this StringBuilder |
| * @throws IndexOutOfBoundsException if beginIndex or endIndex is out of |
| * bounds |
| * @see #substring(int, int) |
| */ |
| public CharSequence subSequence(int beginIndex, int endIndex) |
| { |
| return substring(beginIndex, endIndex); |
| } |
| |
| /** |
| * Creates a substring of this StringBuilder, starting at a specified index |
| * and ending at one character before a specified index. |
| * |
| * @param beginIndex index to start at (inclusive, base 0) |
| * @param endIndex index to end at (exclusive) |
| * @return new String which is a substring of this StringBuilder |
| * @throws StringIndexOutOfBoundsException if beginIndex or endIndex is out |
| * of bounds |
| */ |
| public String substring(int beginIndex, int endIndex) |
| { |
| int len = endIndex - beginIndex; |
| if (beginIndex < 0 || endIndex > count || endIndex < beginIndex) |
| throw new StringIndexOutOfBoundsException(); |
| if (len == 0) |
| return ""; |
| return new String(value, beginIndex, len); |
| } |
| |
| /** |
| * Insert a subarray of the <code>char[]</code> argument into this |
| * <code>StringBuilder</code>. |
| * |
| * @param offset the place to insert in this buffer |
| * @param str the <code>char[]</code> to insert |
| * @param str_offset the index in <code>str</code> to start inserting from |
| * @param len the number of characters to insert |
| * @return this <code>StringBuilder</code> |
| * @throws NullPointerException if <code>str</code> is <code>null</code> |
| * @throws StringIndexOutOfBoundsException if any index is out of bounds |
| */ |
| public StringBuilder insert(int offset, |
| char[] str, int str_offset, int len) |
| { |
| super.insert(offset, str, str_offset, len); |
| return this; |
| } |
| |
| /** |
| * Insert the <code>String</code> value of the argument into this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param offset the place to insert in this buffer |
| * @param obj the <code>Object</code> to convert and insert |
| * @return this <code>StringBuilder</code> |
| * @exception StringIndexOutOfBoundsException if offset is out of bounds |
| * @see String#valueOf(Object) |
| */ |
| public StringBuilder insert(int offset, Object obj) |
| { |
| super.insert(offset, obj); |
| return this; |
| } |
| |
| /** |
| * Insert the <code>String</code> argument into this |
| * <code>StringBuilder</code>. If str is null, the String "null" is used |
| * instead. |
| * |
| * @param offset the place to insert in this buffer |
| * @param str the <code>String</code> to insert |
| * @return this <code>StringBuilder</code> |
| * @throws StringIndexOutOfBoundsException if offset is out of bounds |
| */ |
| public StringBuilder insert(int offset, String str) |
| { |
| super.insert(offset, str); |
| return this; |
| } |
| |
| /** |
| * Insert the <code>CharSequence</code> argument into this |
| * <code>StringBuilder</code>. If the sequence is null, the String |
| * "null" is used instead. |
| * |
| * @param offset the place to insert in this buffer |
| * @param sequence the <code>CharSequence</code> to insert |
| * @return this <code>StringBuilder</code> |
| * @throws IndexOutOfBoundsException if offset is out of bounds |
| */ |
| public StringBuilder insert(int offset, CharSequence sequence) |
| { |
| super.insert(offset, sequence); |
| return this; |
| } |
| |
| /** |
| * Insert a subsequence of the <code>CharSequence</code> argument into this |
| * <code>StringBuilder</code>. If the sequence is null, the String |
| * "null" is used instead. |
| * |
| * @param offset the place to insert in this buffer |
| * @param sequence the <code>CharSequence</code> to insert |
| * @param start the starting index of the subsequence |
| * @param end one past the ending index of the subsequence |
| * @return this <code>StringBuilder</code> |
| * @throws IndexOutOfBoundsException if offset, start, |
| * or end are out of bounds |
| */ |
| public StringBuilder insert(int offset, CharSequence sequence, |
| int start, int end) |
| { |
| super.insert(offset, sequence, start, end); |
| return this; |
| } |
| |
| /** |
| * Insert the <code>char[]</code> argument into this |
| * <code>StringBuilder</code>. |
| * |
| * @param offset the place to insert in this buffer |
| * @param data the <code>char[]</code> to insert |
| * @return this <code>StringBuilder</code> |
| * @throws NullPointerException if <code>data</code> is <code>null</code> |
| * @throws StringIndexOutOfBoundsException if offset is out of bounds |
| * @see #insert(int, char[], int, int) |
| */ |
| public StringBuilder insert(int offset, char[] data) |
| { |
| super.insert(offset, data); |
| return this; |
| } |
| |
| /** |
| * Insert the <code>String</code> value of the argument into this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param offset the place to insert in this buffer |
| * @param bool the <code>boolean</code> to convert and insert |
| * @return this <code>StringBuilder</code> |
| * @throws StringIndexOutOfBoundsException if offset is out of bounds |
| * @see String#valueOf(boolean) |
| */ |
| public StringBuilder insert(int offset, boolean bool) |
| { |
| super.insert(offset, bool); |
| return this; |
| } |
| |
| /** |
| * Insert the <code>char</code> argument into this <code>StringBuilder</code>. |
| * |
| * @param offset the place to insert in this buffer |
| * @param ch the <code>char</code> to insert |
| * @return this <code>StringBuilder</code> |
| * @throws StringIndexOutOfBoundsException if offset is out of bounds |
| */ |
| public StringBuilder insert(int offset, char ch) |
| { |
| super.insert(offset, ch); |
| return this; |
| } |
| |
| /** |
| * Insert the <code>String</code> value of the argument into this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param offset the place to insert in this buffer |
| * @param inum the <code>int</code> to convert and insert |
| * @return this <code>StringBuilder</code> |
| * @throws StringIndexOutOfBoundsException if offset is out of bounds |
| * @see String#valueOf(int) |
| */ |
| public StringBuilder insert(int offset, int inum) |
| { |
| super.insert(offset, inum); |
| return this; |
| } |
| |
| /** |
| * Insert the <code>String</code> value of the argument into this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param offset the place to insert in this buffer |
| * @param lnum the <code>long</code> to convert and insert |
| * @return this <code>StringBuilder</code> |
| * @throws StringIndexOutOfBoundsException if offset is out of bounds |
| * @see String#valueOf(long) |
| */ |
| public StringBuilder insert(int offset, long lnum) |
| { |
| super.insert(offset, lnum); |
| return this; |
| } |
| |
| /** |
| * Insert the <code>String</code> value of the argument into this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param offset the place to insert in this buffer |
| * @param fnum the <code>float</code> to convert and insert |
| * @return this <code>StringBuilder</code> |
| * @throws StringIndexOutOfBoundsException if offset is out of bounds |
| * @see String#valueOf(float) |
| */ |
| public StringBuilder insert(int offset, float fnum) |
| { |
| super.insert(offset, fnum); |
| return this; |
| } |
| |
| /** |
| * Insert the <code>String</code> value of the argument into this |
| * <code>StringBuilder</code>. Uses <code>String.valueOf()</code> to convert |
| * to <code>String</code>. |
| * |
| * @param offset the place to insert in this buffer |
| * @param dnum the <code>double</code> to convert and insert |
| * @return this <code>StringBuilder</code> |
| * @throws StringIndexOutOfBoundsException if offset is out of bounds |
| * @see String#valueOf(double) |
| */ |
| public StringBuilder insert(int offset, double dnum) |
| { |
| super.insert(offset, dnum); |
| return this; |
| } |
| |
| /** |
| * Reverse the characters in this StringBuilder. The same sequence of |
| * characters exists, but in the reverse index ordering. |
| * |
| * @return this <code>StringBuilder</code> |
| */ |
| public StringBuilder reverse() |
| { |
| super.reverse(); |
| return this; |
| } |
| |
| /** |
| * Convert this <code>StringBuilder</code> to a <code>String</code>. The |
| * String is composed of the characters currently in this StringBuilder. Note |
| * that the result is a copy, and that future modifications to this buffer |
| * do not affect the String. |
| * |
| * @return the characters in this StringBuilder |
| */ |
| public String toString() |
| { |
| return new String(this); |
| } |
| |
| } |