Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.commons.lang.text; import java.io.Reader; import java.io.Writer; import java.util.Collection; import java.util.Iterator; import java.util.List; import org.apache.commons.lang.ArrayUtils; /** * Builds a string from constituent parts providing a more flexible and powerful * API than StringBuffer. * <p> * The main differences from StringBuffer/StringBuilder are: * <ul> * <li>Not synchronized</li> * <li>Not final</li> * <li>Subclasses have direct access to character array</li> * <li>Additional methods * <ul> * <li>appendWithSeparators - adds an array of values, with a separator</li> * <li>appendPadding - adds a length padding characters</li> * <li>appendFixedLength - adds a fixed width field to the builder</li> * <li>toCharArray/getChars - simpler ways to get a range of the character array * </li> * <li>delete - delete char or string</li> * <li>replace - search and replace for a char or string</li> * <li>leftString/rightString/midString - substring without exceptions</li> * <li>contains - whether the builder contains a char or string</li> * <li>size/clear/isEmpty - collections style API methods</li> * </ul> * </li> * </ul> * <li>Views * <ul> * <li>asTokenizer - uses the internal buffer as the source of a StrTokenizer</li> * <li>asReader - uses the internal buffer as the source of a Reader</li> * <li>asWriter - allows a Writer to write directly to the internal buffer</li> * </ul> * </li> </ul> * <p> * The aim has been to provide an API that mimics very closely what StringBuffer * provides, but with additional methods. It should be noted that some edge * cases, with invalid indices or null input, have been altered - see individual * methods. The biggest of these changes is that by default, null will not * output the text 'null'. This can be controlled by a property, * {@link #setNullText(String)}. * <p> * Prior to 3.0, this class implemented Cloneable but did not implement the * clone method so could not be used. From 3.0 onwards it no longer implements * the interface. * </p> * * <P> * NOTE: * Modified for Android(TM) platform. by DUMAPIC (http://twitter.com/#!/dumapick) * @modified 2011-05-15 version 1.0.0 * </P> * * @author Apache Software Foundation * @since 2.2 * @version $Id: StrBuilder.java 1057349 2011-01-10 20:40:49Z niallp $ */ public class StrBuilder implements Cloneable { static final String LINE_SEPARATOR = System.getProperty("line.separator"); /** * The extra capacity for new builders. */ static final int CAPACITY = 32; /** * Required for serialization support. * * @see java.io.Serializable */ private static final long serialVersionUID = 7628716375283629643L; /** Internal data storage. */ protected char[] buffer; // TODO make private? /** Current size of the buffer. */ protected int size; // TODO make private? /** The new line. */ private String newLine; /** The null text. */ private String nullText; // ----------------------------------------------------------------------- /** * Constructor that creates an empty builder initial capacity 32 characters. */ public StrBuilder() { this(CAPACITY); } /** * Constructor that creates an empty builder the specified initial capacity. * * @param initialCapacity * the initial capacity, zero or less will be converted to 32 */ public StrBuilder(int initialCapacity) { super(); if (initialCapacity <= 0) { initialCapacity = CAPACITY; } buffer = new char[initialCapacity]; } /** * Constructor that creates a builder from the string, allocating 32 extra * characters for growth. * * @param str * the string to copy, null treated as blank string */ public StrBuilder(String str) { super(); if (str == null) { buffer = new char[CAPACITY]; } else { buffer = new char[str.length() + CAPACITY]; append(str); } } // ----------------------------------------------------------------------- /** * Gets the text to be appended when a new line is added. * * @return the new line text, null means use system default */ public String getNewLineText() { return newLine; } /** * Sets the text to be appended when a new line is added. * * @param newLine * the new line text, null means use system default * @return this, to enable chaining */ public StrBuilder setNewLineText(String newLine) { this.newLine = newLine; return this; } // ----------------------------------------------------------------------- /** * Gets the text to be appended when null is added. * * @return the null text, null means no append */ public String getNullText() { return nullText; } /** * Sets the text to be appended when null is added. * * @param nullText * the null text, null means no append * @return this, to enable chaining */ public StrBuilder setNullText(String nullText) { if (nullText != null && nullText.length() == 0) { nullText = null; } this.nullText = nullText; return this; } // ----------------------------------------------------------------------- /** * Gets the length of the string builder. * * @return the length */ public int length() { return size; } /** * Updates the length of the builder by either dropping the last characters * or adding filler of unicode zero. * * @param length * the length to set to, must be zero or positive * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the length is negative */ public StrBuilder setLength(int length) { if (length < 0) { throw new StringIndexOutOfBoundsException(length); } if (length < size) { size = length; } else if (length > size) { ensureCapacity(length); int oldEnd = size; int newEnd = length; size = length; for (int i = oldEnd; i < newEnd; i++) { buffer[i] = '\0'; } } return this; } // ----------------------------------------------------------------------- /** * Gets the current size of the internal character array buffer. * * @return the capacity */ public int capacity() { return buffer.length; } /** * Checks the capacity and ensures that it is at least the size specified. * * @param capacity * the capacity to ensure * @return this, to enable chaining */ public StrBuilder ensureCapacity(int capacity) { if (capacity > buffer.length) { char[] old = buffer; buffer = new char[capacity * 2]; System.arraycopy(old, 0, buffer, 0, size); } return this; } /** * Minimizes the capacity to the actual length of the string. * * @return this, to enable chaining */ public StrBuilder minimizeCapacity() { if (buffer.length > length()) { char[] old = buffer; buffer = new char[length()]; System.arraycopy(old, 0, buffer, 0, size); } return this; } // ----------------------------------------------------------------------- /** * Gets the length of the string builder. * <p> * This method is the same as {@link #length()} and is provided to match the * API of Collections. * * @return the length */ public int size() { return size; } /** * Checks is the string builder is empty (convenience Collections API style * method). * <p> * This method is the same as checking {@link #length()} and is provided to * match the API of Collections. * * @return <code>true</code> if the size is <code>0</code>. */ public boolean isEmpty() { return size == 0; } /** * Clears the string builder (convenience Collections API style method). * <p> * This method does not reduce the size of the internal character buffer. To * do that, call <code>clear()</code> followed by * {@link #minimizeCapacity()}. * <p> * This method is the same as {@link #setLength(int)} called with zero and * is provided to match the API of Collections. * * @return this, to enable chaining */ public StrBuilder clear() { size = 0; return this; } // ----------------------------------------------------------------------- /** * Gets the character at the specified index. * * @see #setCharAt(int, char) * @see #deleteCharAt(int) * @param index * the index to retrieve, must be valid * @return the character at the index * @throws IndexOutOfBoundsException * if the index is invalid */ public char charAt(int index) { if (index < 0 || index >= length()) { throw new StringIndexOutOfBoundsException(index); } return buffer[index]; } /** * Sets the character at the specified index. * * @see #charAt(int) * @see #deleteCharAt(int) * @param index * the index to set * @param ch * the new character * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder setCharAt(int index, char ch) { if (index < 0 || index >= length()) { throw new StringIndexOutOfBoundsException(index); } buffer[index] = ch; return this; } /** * Deletes the character at the specified index. * * @see #charAt(int) * @see #setCharAt(int, char) * @param index * the index to delete * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder deleteCharAt(int index) { if (index < 0 || index >= size) { throw new StringIndexOutOfBoundsException(index); } deleteImpl(index, index + 1, 1); return this; } // ----------------------------------------------------------------------- /** * Copies the builder's character array into a new character array. * * @return a new array that represents the contents of the builder */ public char[] toCharArray() { if (size == 0) { return ArrayUtils.EMPTY_CHAR_ARRAY; } char chars[] = new char[size]; System.arraycopy(buffer, 0, chars, 0, size); return chars; } /** * Copies part of the builder's character array into a new character array. * * @param startIndex * the start index, inclusive, must be valid * @param endIndex * the end index, exclusive, must be valid except that if too * large it is treated as end of string * @return a new array that holds part of the contents of the builder * @throws IndexOutOfBoundsException * if startIndex is invalid, or if endIndex is invalid (but * endIndex greater than size is valid) */ public char[] toCharArray(int startIndex, int endIndex) { endIndex = validateRange(startIndex, endIndex); int len = endIndex - startIndex; if (len == 0) { return ArrayUtils.EMPTY_CHAR_ARRAY; } char chars[] = new char[len]; System.arraycopy(buffer, startIndex, chars, 0, len); return chars; } /** * Copies the character array into the specified array. * * @param destination * the destination array, null will cause an array to be created * @return the input array, unless that was null or too small */ public char[] getChars(char[] destination) { int len = length(); if (destination == null || destination.length < len) { destination = new char[len]; } System.arraycopy(buffer, 0, destination, 0, len); return destination; } /** * Copies the character array into the specified array. * * @param startIndex * first index to copy, inclusive, must be valid * @param endIndex * last index, exclusive, must be valid * @param destination * the destination array, must not be null or too small * @param destinationIndex * the index to start copying in destination * @throws NullPointerException * if the array is null * @throws IndexOutOfBoundsException * if any index is invalid */ public void getChars(int startIndex, int endIndex, char destination[], int destinationIndex) { if (startIndex < 0) { throw new StringIndexOutOfBoundsException(startIndex); } if (endIndex < 0 || endIndex > length()) { throw new StringIndexOutOfBoundsException(endIndex); } if (startIndex > endIndex) { throw new StringIndexOutOfBoundsException("end < start"); } System.arraycopy(buffer, startIndex, destination, destinationIndex, endIndex - startIndex); } // ----------------------------------------------------------------------- /** * Appends the new line string to this string builder. * <p> * The new line string can be altered using {@link #setNewLineText(String)}. * This might be used to force the output to always use Unix line endings * even when on Windows. * * @return this, to enable chaining */ public StrBuilder appendNewLine() { if (newLine == null) { append(LINE_SEPARATOR); return this; } return append(newLine); } /** * Appends the text representing <code>null</code> to this string builder. * * @return this, to enable chaining */ public StrBuilder appendNull() { if (nullText == null) { return this; } return append(nullText); } /** * Appends an object to this string builder. Appending null will call * {@link #appendNull()}. * * @param obj * the object to append * @return this, to enable chaining */ public StrBuilder append(Object obj) { if (obj == null) { return appendNull(); } return append(obj.toString()); } /** * Appends a string to this string builder. Appending null will call * {@link #appendNull()}. * * @param str * the string to append * @return this, to enable chaining */ public StrBuilder append(String str) { if (str == null) { return appendNull(); } int strLen = str.length(); if (strLen > 0) { int len = length(); ensureCapacity(len + strLen); str.getChars(0, strLen, buffer, len); size += strLen; } return this; } /** * Appends part of a string to this string builder. Appending null will call * {@link #appendNull()}. * * @param str * the string to append * @param startIndex * the start index, inclusive, must be valid * @param length * the length to append, must be valid * @return this, to enable chaining */ public StrBuilder append(String str, int startIndex, int length) { if (str == null) { return appendNull(); } if (startIndex < 0 || startIndex > str.length()) { throw new StringIndexOutOfBoundsException("startIndex must be valid"); } if (length < 0 || (startIndex + length) > str.length()) { throw new StringIndexOutOfBoundsException("length must be valid"); } if (length > 0) { int len = length(); ensureCapacity(len + length); str.getChars(startIndex, startIndex + length, buffer, len); size += length; } return this; } /** * Appends a string buffer to this string builder. Appending null will call * {@link #appendNull()}. * * @param str * the string buffer to append * @return this, to enable chaining */ public StrBuilder append(StringBuffer str) { if (str == null) { return appendNull(); } int strLen = str.length(); if (strLen > 0) { int len = length(); ensureCapacity(len + strLen); str.getChars(0, strLen, buffer, len); size += strLen; } return this; } /** * Appends part of a string buffer to this string builder. Appending null * will call {@link #appendNull()}. * * @param str * the string to append * @param startIndex * the start index, inclusive, must be valid * @param length * the length to append, must be valid * @return this, to enable chaining */ public StrBuilder append(StringBuffer str, int startIndex, int length) { if (str == null) { return appendNull(); } if (startIndex < 0 || startIndex > str.length()) { throw new StringIndexOutOfBoundsException("startIndex must be valid"); } if (length < 0 || (startIndex + length) > str.length()) { throw new StringIndexOutOfBoundsException("length must be valid"); } if (length > 0) { int len = length(); ensureCapacity(len + length); str.getChars(startIndex, startIndex + length, buffer, len); size += length; } return this; } /** * Appends another string builder to this string builder. Appending null * will call {@link #appendNull()}. * * @param str * the string builder to append * @return this, to enable chaining */ public StrBuilder append(StrBuilder str) { if (str == null) { return appendNull(); } int strLen = str.length(); if (strLen > 0) { int len = length(); ensureCapacity(len + strLen); System.arraycopy(str.buffer, 0, buffer, len, strLen); size += strLen; } return this; } /** * Appends part of a string builder to this string builder. Appending null * will call {@link #appendNull()}. * * @param str * the string to append * @param startIndex * the start index, inclusive, must be valid * @param length * the length to append, must be valid * @return this, to enable chaining */ public StrBuilder append(StrBuilder str, int startIndex, int length) { if (str == null) { return appendNull(); } if (startIndex < 0 || startIndex > str.length()) { throw new StringIndexOutOfBoundsException("startIndex must be valid"); } if (length < 0 || (startIndex + length) > str.length()) { throw new StringIndexOutOfBoundsException("length must be valid"); } if (length > 0) { int len = length(); ensureCapacity(len + length); str.getChars(startIndex, startIndex + length, buffer, len); size += length; } return this; } /** * Appends a char array to the string builder. Appending null will call * {@link #appendNull()}. * * @param chars * the char array to append * @return this, to enable chaining */ public StrBuilder append(char[] chars) { if (chars == null) { return appendNull(); } int strLen = chars.length; if (strLen > 0) { int len = length(); ensureCapacity(len + strLen); System.arraycopy(chars, 0, buffer, len, strLen); size += strLen; } return this; } /** * Appends a char array to the string builder. Appending null will call * {@link #appendNull()}. * * @param chars * the char array to append * @param startIndex * the start index, inclusive, must be valid * @param length * the length to append, must be valid * @return this, to enable chaining */ public StrBuilder append(char[] chars, int startIndex, int length) { if (chars == null) { return appendNull(); } if (startIndex < 0 || startIndex > chars.length) { throw new StringIndexOutOfBoundsException("Invalid startIndex: " + length); } if (length < 0 || (startIndex + length) > chars.length) { throw new StringIndexOutOfBoundsException("Invalid length: " + length); } if (length > 0) { int len = length(); ensureCapacity(len + length); System.arraycopy(chars, startIndex, buffer, len, length); size += length; } return this; } /** * Appends a boolean value to the string builder. * * @param value * the value to append * @return this, to enable chaining */ public StrBuilder append(boolean value) { if (value) { ensureCapacity(size + 4); buffer[size++] = 't'; buffer[size++] = 'r'; buffer[size++] = 'u'; buffer[size++] = 'e'; } else { ensureCapacity(size + 5); buffer[size++] = 'f'; buffer[size++] = 'a'; buffer[size++] = 'l'; buffer[size++] = 's'; buffer[size++] = 'e'; } return this; } /** * Appends a char value to the string builder. * * @param ch * the value to append * @return this, to enable chaining */ public StrBuilder append(char ch) { int len = length(); ensureCapacity(len + 1); buffer[size++] = ch; return this; } /** * Appends an int value to the string builder using * <code>String.valueOf</code>. * * @param value * the value to append * @return this, to enable chaining */ public StrBuilder append(int value) { return append(String.valueOf(value)); } /** * Appends a long value to the string builder using * <code>String.valueOf</code>. * * @param value * the value to append * @return this, to enable chaining */ public StrBuilder append(long value) { return append(String.valueOf(value)); } /** * Appends a float value to the string builder using * <code>String.valueOf</code>. * * @param value * the value to append * @return this, to enable chaining */ public StrBuilder append(float value) { return append(String.valueOf(value)); } /** * Appends a double value to the string builder using * <code>String.valueOf</code>. * * @param value * the value to append * @return this, to enable chaining */ public StrBuilder append(double value) { return append(String.valueOf(value)); } // ----------------------------------------------------------------------- /** * Appends an object followed by a new line to this string builder. * Appending null will call {@link #appendNull()}. * * @param obj * the object to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(Object obj) { return append(obj).appendNewLine(); } /** * Appends a string followed by a new line to this string builder. Appending * null will call {@link #appendNull()}. * * @param str * the string to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(String str) { return append(str).appendNewLine(); } /** * Appends part of a string followed by a new line to this string builder. * Appending null will call {@link #appendNull()}. * * @param str * the string to append * @param startIndex * the start index, inclusive, must be valid * @param length * the length to append, must be valid * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(String str, int startIndex, int length) { return append(str, startIndex, length).appendNewLine(); } /** * Appends a string buffer followed by a new line to this string builder. * Appending null will call {@link #appendNull()}. * * @param str * the string buffer to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(StringBuffer str) { return append(str).appendNewLine(); } /** * Appends part of a string buffer followed by a new line to this string * builder. Appending null will call {@link #appendNull()}. * * @param str * the string to append * @param startIndex * the start index, inclusive, must be valid * @param length * the length to append, must be valid * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(StringBuffer str, int startIndex, int length) { return append(str, startIndex, length).appendNewLine(); } /** * Appends another string builder followed by a new line to this string * builder. Appending null will call {@link #appendNull()}. * * @param str * the string builder to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(StrBuilder str) { return append(str).appendNewLine(); } /** * Appends part of a string builder followed by a new line to this string * builder. Appending null will call {@link #appendNull()}. * * @param str * the string to append * @param startIndex * the start index, inclusive, must be valid * @param length * the length to append, must be valid * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(StrBuilder str, int startIndex, int length) { return append(str, startIndex, length).appendNewLine(); } /** * Appends a char array followed by a new line to the string builder. * Appending null will call {@link #appendNull()}. * * @param chars * the char array to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(char[] chars) { return append(chars).appendNewLine(); } /** * Appends a char array followed by a new line to the string builder. * Appending null will call {@link #appendNull()}. * * @param chars * the char array to append * @param startIndex * the start index, inclusive, must be valid * @param length * the length to append, must be valid * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(char[] chars, int startIndex, int length) { return append(chars, startIndex, length).appendNewLine(); } /** * Appends a boolean value followed by a new line to the string builder. * * @param value * the value to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(boolean value) { return append(value).appendNewLine(); } /** * Appends a char value followed by a new line to the string builder. * * @param ch * the value to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(char ch) { return append(ch).appendNewLine(); } /** * Appends an int value followed by a new line to the string builder using * <code>String.valueOf</code>. * * @param value * the value to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(int value) { return append(value).appendNewLine(); } /** * Appends a long value followed by a new line to the string builder using * <code>String.valueOf</code>. * * @param value * the value to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(long value) { return append(value).appendNewLine(); } /** * Appends a float value followed by a new line to the string builder using * <code>String.valueOf</code>. * * @param value * the value to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(float value) { return append(value).appendNewLine(); } /** * Appends a double value followed by a new line to the string builder using * <code>String.valueOf</code>. * * @param value * the value to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendln(double value) { return append(value).appendNewLine(); } // ----------------------------------------------------------------------- /** * Appends each item in an array to the builder without any separators. * Appending a null array will have no effect. Each object is appended using * {@link #append(Object)}. * * @param array * the array to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendAll(Object[] array) { if (array != null && array.length > 0) { for (int i = 0; i < array.length; i++) { append(array[i]); } } return this; } /** * Appends each item in a collection to the builder without any separators. * Appending a null collection will have no effect. Each object is appended * using {@link #append(Object)}. * * @param coll * the collection to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendAll(Collection<?> coll) { if (coll != null && coll.size() > 0) { Iterator<?> it = coll.iterator(); while (it.hasNext()) { append(it.next()); } } return this; } /** * Appends each item in an iterator to the builder without any separators. * Appending a null iterator will have no effect. Each object is appended * using {@link #append(Object)}. * * @param it * the iterator to append * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendAll(Iterator<?> it) { if (it != null) { while (it.hasNext()) { append(it.next()); } } return this; } // ----------------------------------------------------------------------- /** * Appends an array placing separators between each value, but not before * the first or after the last. Appending a null array will have no effect. * Each object is appended using {@link #append(Object)}. * * @param array * the array to append * @param separator * the separator to use, null means no separator * @return this, to enable chaining */ public StrBuilder appendWithSeparators(Object[] array, String separator) { if (array != null && array.length > 0) { separator = (separator == null ? "" : separator); append(array[0]); for (int i = 1; i < array.length; i++) { append(separator); append(array[i]); } } return this; } /** * Appends a collection placing separators between each value, but not * before the first or after the last. Appending a null collection will have * no effect. Each object is appended using {@link #append(Object)}. * * @param coll * the collection to append * @param separator * the separator to use, null means no separator * @return this, to enable chaining */ public StrBuilder appendWithSeparators(Collection<?> coll, String separator) { if (coll != null && coll.size() > 0) { separator = (separator == null ? "" : separator); Iterator<?> it = coll.iterator(); while (it.hasNext()) { append(it.next()); if (it.hasNext()) { append(separator); } } } return this; } /** * Appends an iterator placing separators between each value, but not before * the first or after the last. Appending a null iterator will have no * effect. Each object is appended using {@link #append(Object)}. * * @param it * the iterator to append * @param separator * the separator to use, null means no separator * @return this, to enable chaining */ public StrBuilder appendWithSeparators(Iterator<?> it, String separator) { if (it != null) { separator = (separator == null ? "" : separator); while (it.hasNext()) { append(it.next()); if (it.hasNext()) { append(separator); } } } return this; } // ----------------------------------------------------------------------- /** * Appends a separator if the builder is currently non-empty. Appending a * null separator will have no effect. The separator is appended using * {@link #append(String)}. * <p> * This method is useful for adding a separator each time around the loop * except the first. * * <pre> * for (Iterator it = list.iterator(); it.hasNext();) * { * appendSeparator(","); * append(it.next()); * } * </pre> * * Note that for this simple example, you should use * {@link #appendWithSeparators(Collection, String)}. * * @param separator * the separator to use, null means no separator * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendSeparator(String separator) { return appendSeparator(separator, null); } /** * Appends one of both separators to the StrBuilder. If the builder is * currently empty it will append the defaultIfEmpty-separator Otherwise it * will append the standard-separator * * Appending a null separator will have no effect. The separator is appended * using {@link #append(String)}. * <p> * This method is for example useful for constructing queries * * <pre> * StrBuilder whereClause = new StrBuilder(); * if(searchCommand.getPriority() != null) { * whereClause.appendSeparator(" and", " where"); * whereClause.append(" priority = ?") * } * if(searchCommand.getComponent() != null) { * whereClause.appendSeparator(" and", " where"); * whereClause.append(" component = ?") * } * selectClause.append(whereClause) * </pre> * * @param standard * the separator if builder is not empty, null means no separator * @param defaultIfEmpty * the separator if builder is empty, null means no separator * @return this, to enable chaining * @since 2.5 */ public StrBuilder appendSeparator(String standard, String defaultIfEmpty) { String str = isEmpty() ? defaultIfEmpty : standard; if (str != null) { append(str); } return this; } /** * Appends a separator if the builder is currently non-empty. The separator * is appended using {@link #append(char)}. * <p> * This method is useful for adding a separator each time around the loop * except the first. * * <pre> * for (Iterator it = list.iterator(); it.hasNext();) * { * appendSeparator(','); * append(it.next()); * } * </pre> * * Note that for this simple example, you should use * {@link #appendWithSeparators(Collection, String)}. * * @param separator * the separator to use * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendSeparator(char separator) { if (size() > 0) { append(separator); } return this; } /** * Append one of both separators to the builder If the builder is currently * empty it will append the defaultIfEmpty-separator Otherwise it will * append the standard-separator * * The separator is appended using {@link #append(char)}. * * @param standard * the separator if builder is not empty * @param defaultIfEmpty * the separator if builder is empty * @return this, to enable chaining * @since 2.5 */ public StrBuilder appendSeparator(char standard, char defaultIfEmpty) { if (size() > 0) { append(standard); } else { append(defaultIfEmpty); } return this; } /** * Appends a separator to the builder if the loop index is greater than * zero. Appending a null separator will have no effect. The separator is * appended using {@link #append(String)}. * <p> * This method is useful for adding a separator each time around the loop * except the first. * * <pre> * for (int i = 0; i < list.size(); i++) * { * appendSeparator(",", i); * append(list.get(i)); * } * </pre> * * Note that for this simple example, you should use * {@link #appendWithSeparators(Collection, String)}. * * @param separator * the separator to use, null means no separator * @param loopIndex * the loop index * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendSeparator(String separator, int loopIndex) { if (separator != null && loopIndex > 0) { append(separator); } return this; } /** * Appends a separator to the builder if the loop index is greater than * zero. The separator is appended using {@link #append(char)}. * <p> * This method is useful for adding a separator each time around the loop * except the first. * * <pre> * for (int i = 0; i < list.size(); i++) * { * appendSeparator(",", i); * append(list.get(i)); * } * </pre> * * Note that for this simple example, you should use * {@link #appendWithSeparators(Collection, String)}. * * @param separator * the separator to use * @param loopIndex * the loop index * @return this, to enable chaining * @since 2.3 */ public StrBuilder appendSeparator(char separator, int loopIndex) { if (loopIndex > 0) { append(separator); } return this; } // ----------------------------------------------------------------------- /** * Appends the pad character to the builder the specified number of times. * * @param length * the length to append, negative means no append * @param padChar * the character to append * @return this, to enable chaining */ public StrBuilder appendPadding(int length, char padChar) { if (length >= 0) { ensureCapacity(size + length); for (int i = 0; i < length; i++) { buffer[size++] = padChar; } } return this; } // ----------------------------------------------------------------------- /** * Appends an object to the builder padding on the left to a fixed width. * The <code>toString</code> of the object is used. If the object is larger * than the length, the left hand side is lost. If the object is null, the * null text value is used. * * @param obj * the object to append, null uses null text * @param width * the fixed field width, zero or negative has no effect * @param padChar * the pad character to use * @return this, to enable chaining */ public StrBuilder appendFixedWidthPadLeft(Object obj, int width, char padChar) { if (width > 0) { ensureCapacity(size + width); String str = (obj == null ? getNullText() : obj.toString()); if (str == null) { str = ""; } int strLen = str.length(); if (strLen >= width) { str.getChars(strLen - width, strLen, buffer, size); } else { int padLen = width - strLen; for (int i = 0; i < padLen; i++) { buffer[size + i] = padChar; } str.getChars(0, strLen, buffer, size + padLen); } size += width; } return this; } /** * Appends an object to the builder padding on the left to a fixed width. * The <code>String.valueOf</code> of the <code>int</code> value is used. If * the formatted value is larger than the length, the left hand side is * lost. * * @param value * the value to append * @param width * the fixed field width, zero or negative has no effect * @param padChar * the pad character to use * @return this, to enable chaining */ public StrBuilder appendFixedWidthPadLeft(int value, int width, char padChar) { return appendFixedWidthPadLeft(String.valueOf(value), width, padChar); } /** * Appends an object to the builder padding on the right to a fixed length. * The <code>toString</code> of the object is used. If the object is larger * than the length, the right hand side is lost. If the object is null, null * text value is used. * * @param obj * the object to append, null uses null text * @param width * the fixed field width, zero or negative has no effect * @param padChar * the pad character to use * @return this, to enable chaining */ public StrBuilder appendFixedWidthPadRight(Object obj, int width, char padChar) { if (width > 0) { ensureCapacity(size + width); String str = (obj == null ? getNullText() : obj.toString()); if (str == null) { str = ""; } int strLen = str.length(); if (strLen >= width) { str.getChars(0, width, buffer, size); } else { int padLen = width - strLen; str.getChars(0, strLen, buffer, size); for (int i = 0; i < padLen; i++) { buffer[size + strLen + i] = padChar; } } size += width; } return this; } /** * Appends an object to the builder padding on the right to a fixed length. * The <code>String.valueOf</code> of the <code>int</code> value is used. If * the object is larger than the length, the right hand side is lost. * * @param value * the value to append * @param width * the fixed field width, zero or negative has no effect * @param padChar * the pad character to use * @return this, to enable chaining */ public StrBuilder appendFixedWidthPadRight(int value, int width, char padChar) { return appendFixedWidthPadRight(String.valueOf(value), width, padChar); } // ----------------------------------------------------------------------- /** * Inserts the string representation of an object into this builder. * Inserting null will use the stored null text value. * * @param index * the index to add at, must be valid * @param obj * the object to insert * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder insert(int index, Object obj) { if (obj == null) { return insert(index, nullText); } return insert(index, obj.toString()); } /** * Inserts the string into this builder. Inserting null will use the stored * null text value. * * @param index * the index to add at, must be valid * @param str * the string to insert * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder insert(int index, String str) { validateIndex(index); if (str == null) { str = nullText; } int strLen = (str == null ? 0 : str.length()); if (strLen > 0) { int newSize = size + strLen; ensureCapacity(newSize); System.arraycopy(buffer, index, buffer, index + strLen, size - index); size = newSize; str.getChars(0, strLen, buffer, index); // str cannot be null here } return this; } /** * Inserts the character array into this builder. Inserting null will use * the stored null text value. * * @param index * the index to add at, must be valid * @param chars * the char array to insert * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder insert(int index, char chars[]) { validateIndex(index); if (chars == null) { return insert(index, nullText); } int len = chars.length; if (len > 0) { ensureCapacity(size + len); System.arraycopy(buffer, index, buffer, index + len, size - index); System.arraycopy(chars, 0, buffer, index, len); size += len; } return this; } /** * Inserts part of the character array into this builder. Inserting null * will use the stored null text value. * * @param index * the index to add at, must be valid * @param chars * the char array to insert * @param offset * the offset into the character array to start at, must be valid * @param length * the length of the character array part to copy, must be * positive * @return this, to enable chaining * @throws IndexOutOfBoundsException * if any index is invalid */ public StrBuilder insert(int index, char chars[], int offset, int length) { validateIndex(index); if (chars == null) { return insert(index, nullText); } if (offset < 0 || offset > chars.length) { throw new StringIndexOutOfBoundsException("Invalid offset: " + offset); } if (length < 0 || offset + length > chars.length) { throw new StringIndexOutOfBoundsException("Invalid length: " + length); } if (length > 0) { ensureCapacity(size + length); System.arraycopy(buffer, index, buffer, index + length, size - index); System.arraycopy(chars, offset, buffer, index, length); size += length; } return this; } /** * Inserts the value into this builder. * * @param index * the index to add at, must be valid * @param value * the value to insert * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder insert(int index, boolean value) { validateIndex(index); if (value) { ensureCapacity(size + 4); System.arraycopy(buffer, index, buffer, index + 4, size - index); buffer[index++] = 't'; buffer[index++] = 'r'; buffer[index++] = 'u'; buffer[index] = 'e'; size += 4; } else { ensureCapacity(size + 5); System.arraycopy(buffer, index, buffer, index + 5, size - index); buffer[index++] = 'f'; buffer[index++] = 'a'; buffer[index++] = 'l'; buffer[index++] = 's'; buffer[index] = 'e'; size += 5; } return this; } /** * Inserts the value into this builder. * * @param index * the index to add at, must be valid * @param value * the value to insert * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder insert(int index, char value) { validateIndex(index); ensureCapacity(size + 1); System.arraycopy(buffer, index, buffer, index + 1, size - index); buffer[index] = value; size++; return this; } /** * Inserts the value into this builder. * * @param index * the index to add at, must be valid * @param value * the value to insert * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder insert(int index, int value) { return insert(index, String.valueOf(value)); } /** * Inserts the value into this builder. * * @param index * the index to add at, must be valid * @param value * the value to insert * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder insert(int index, long value) { return insert(index, String.valueOf(value)); } /** * Inserts the value into this builder. * * @param index * the index to add at, must be valid * @param value * the value to insert * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder insert(int index, float value) { return insert(index, String.valueOf(value)); } /** * Inserts the value into this builder. * * @param index * the index to add at, must be valid * @param value * the value to insert * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder insert(int index, double value) { return insert(index, String.valueOf(value)); } // ----------------------------------------------------------------------- /** * Internal method to delete a range without validation. * * @param startIndex * the start index, must be valid * @param endIndex * the end index (exclusive), must be valid * @param len * the length, must be valid * @throws IndexOutOfBoundsException * if any index is invalid */ private void deleteImpl(int startIndex, int endIndex, int len) { System.arraycopy(buffer, endIndex, buffer, startIndex, size - endIndex); size -= len; } /** * Deletes the characters between the two specified indices. * * @param startIndex * the start index, inclusive, must be valid * @param endIndex * the end index, exclusive, must be valid except that if too * large it is treated as end of string * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder delete(int startIndex, int endIndex) { endIndex = validateRange(startIndex, endIndex); int len = endIndex - startIndex; if (len > 0) { deleteImpl(startIndex, endIndex, len); } return this; } // ----------------------------------------------------------------------- /** * Deletes the character wherever it occurs in the builder. * * @param ch * the character to delete * @return this, to enable chaining */ public StrBuilder deleteAll(char ch) { for (int i = 0; i < size; i++) { if (buffer[i] == ch) { int start = i; while (++i < size) { if (buffer[i] != ch) { break; } } int len = i - start; deleteImpl(start, i, len); i -= len; } } return this; } /** * Deletes the character wherever it occurs in the builder. * * @param ch * the character to delete * @return this, to enable chaining */ public StrBuilder deleteFirst(char ch) { for (int i = 0; i < size; i++) { if (buffer[i] == ch) { deleteImpl(i, i + 1, 1); break; } } return this; } // ----------------------------------------------------------------------- /** * Deletes the string wherever it occurs in the builder. * * @param str * the string to delete, null causes no action * @return this, to enable chaining */ public StrBuilder deleteAll(String str) { int len = (str == null ? 0 : str.length()); if (len > 0) { int index = indexOf(str, 0); while (index >= 0) { deleteImpl(index, index + len, len); index = indexOf(str, index); } } return this; } /** * Deletes the string wherever it occurs in the builder. * * @param str * the string to delete, null causes no action * @return this, to enable chaining */ public StrBuilder deleteFirst(String str) { int len = (str == null ? 0 : str.length()); if (len > 0) { int index = indexOf(str, 0); if (index >= 0) { deleteImpl(index, index + len, len); } } return this; } // ----------------------------------------------------------------------- /** * Deletes all parts of the builder that the matcher matches. * <p> * Matchers can be used to perform advanced deletion behaviour. For example * you could write a matcher to delete all occurances where the character * 'a' is followed by a number. * * @param matcher * the matcher to use to find the deletion, null causes no action * @return this, to enable chaining */ public StrBuilder deleteAll(StrMatcher matcher) { return replace(matcher, null, 0, size, -1); } /** * Deletes the first match within the builder using the specified matcher. * <p> * Matchers can be used to perform advanced deletion behaviour. For example * you could write a matcher to delete where the character 'a' is followed * by a number. * * @param matcher * the matcher to use to find the deletion, null causes no action * @return this, to enable chaining */ public StrBuilder deleteFirst(StrMatcher matcher) { return replace(matcher, null, 0, size, 1); } // ----------------------------------------------------------------------- /** * Internal method to delete a range without validation. * * @param startIndex * the start index, must be valid * @param endIndex * the end index (exclusive), must be valid * @param removeLen * the length to remove (endIndex - startIndex), must be valid * @param insertStr * the string to replace with, null means delete range * @param insertLen * the length of the insert string, must be valid * @throws IndexOutOfBoundsException * if any index is invalid */ private void replaceImpl(int startIndex, int endIndex, int removeLen, String insertStr, int insertLen) { int newSize = size - removeLen + insertLen; if (insertLen != removeLen) { ensureCapacity(newSize); System.arraycopy(buffer, endIndex, buffer, startIndex + insertLen, size - endIndex); size = newSize; } if (insertLen > 0) { insertStr.getChars(0, insertLen, buffer, startIndex); } } /** * Replaces a portion of the string builder with another string. The length * of the inserted string does not have to match the removed length. * * @param startIndex * the start index, inclusive, must be valid * @param endIndex * the end index, exclusive, must be valid except that if too * large it is treated as end of string * @param replaceStr * the string to replace with, null means delete range * @return this, to enable chaining * @throws IndexOutOfBoundsException * if the index is invalid */ public StrBuilder replace(int startIndex, int endIndex, String replaceStr) { endIndex = validateRange(startIndex, endIndex); int insertLen = (replaceStr == null ? 0 : replaceStr.length()); replaceImpl(startIndex, endIndex, endIndex - startIndex, replaceStr, insertLen); return this; } // ----------------------------------------------------------------------- /** * Replaces the search character with the replace character throughout the * builder. * * @param search * the search character * @param replace * the replace character * @return this, to enable chaining */ public StrBuilder replaceAll(char search, char replace) { if (search != replace) { for (int i = 0; i < size; i++) { if (buffer[i] == search) { buffer[i] = replace; } } } return this; } /** * Replaces the first instance of the search character with the replace * character in the builder. * * @param search * the search character * @param replace * the replace character * @return this, to enable chaining */ public StrBuilder replaceFirst(char search, char replace) { if (search != replace) { for (int i = 0; i < size; i++) { if (buffer[i] == search) { buffer[i] = replace; break; } } } return this; } // ----------------------------------------------------------------------- /** * Replaces the search string with the replace string throughout the * builder. * * @param searchStr * the search string, null causes no action to occur * @param replaceStr * the replace string, null is equivalent to an empty string * @return this, to enable chaining */ public StrBuilder replaceAll(String searchStr, String replaceStr) { int searchLen = (searchStr == null ? 0 : searchStr.length()); if (searchLen > 0) { int replaceLen = (replaceStr == null ? 0 : replaceStr.length()); int index = indexOf(searchStr, 0); while (index >= 0) { replaceImpl(index, index + searchLen, searchLen, replaceStr, replaceLen); index = indexOf(searchStr, index + replaceLen); } } return this; } /** * Replaces the first instance of the search string with the replace string. * * @param searchStr * the search string, null causes no action to occur * @param replaceStr * the replace string, null is equivalent to an empty string * @return this, to enable chaining */ public StrBuilder replaceFirst(String searchStr, String replaceStr) { int searchLen = (searchStr == null ? 0 : searchStr.length()); if (searchLen > 0) { int index = indexOf(searchStr, 0); if (index >= 0) { int replaceLen = (replaceStr == null ? 0 : replaceStr.length()); replaceImpl(index, index + searchLen, searchLen, replaceStr, replaceLen); } } return this; } // ----------------------------------------------------------------------- /** * Replaces all matches within the builder with the replace string. * <p> * Matchers can be used to perform advanced replace behaviour. For example * you could write a matcher to replace all occurances where the character * 'a' is followed by a number. * * @param matcher * the matcher to use to find the deletion, null causes no action * @param replaceStr * the replace string, null is equivalent to an empty string * @return this, to enable chaining */ public StrBuilder replaceAll(StrMatcher matcher, String replaceStr) { return replace(matcher, replaceStr, 0, size, -1); } /** * Replaces the first match within the builder with the replace string. * <p> * Matchers can be used to perform advanced replace behaviour. For example * you could write a matcher to replace where the character 'a' is followed * by a number. * * @param matcher * the matcher to use to find the deletion, null causes no action * @param replaceStr * the replace string, null is equivalent to an empty string * @return this, to enable chaining */ public StrBuilder replaceFirst(StrMatcher matcher, String replaceStr) { return replace(matcher, replaceStr, 0, size, 1); } // ----------------------------------------------------------------------- /** * Advanced search and replaces within the builder using a matcher. * <p> * Matchers can be used to perform advanced behaviour. For example you could * write a matcher to delete all occurances where the character 'a' is * followed by a number. * * @param matcher * the matcher to use to find the deletion, null causes no action * @param replaceStr * the string to replace the match with, null is a delete * @param startIndex * the start index, inclusive, must be valid * @param endIndex * the end index, exclusive, must be valid except that if too * large it is treated as end of string * @param replaceCount * the number of times to replace, -1 for replace all * @return this, to enable chaining * @throws IndexOutOfBoundsException * if start index is invalid */ public StrBuilder replace(StrMatcher matcher, String replaceStr, int startIndex, int endIndex, int replaceCount) { endIndex = validateRange(startIndex, endIndex); return replaceImpl(matcher, replaceStr, startIndex, endIndex, replaceCount); } /** * Replaces within the builder using a matcher. * <p> * Matchers can be used to perform advanced behaviour. For example you could * write a matcher to delete all occurances where the character 'a' is * followed by a number. * * @param matcher * the matcher to use to find the deletion, null causes no action * @param replaceStr * the string to replace the match with, null is a delete * @param from * the start index, must be valid * @param to * the end index (exclusive), must be valid * @param replaceCount * the number of times to replace, -1 for replace all * @return this, to enable chaining * @throws IndexOutOfBoundsException * if any index is invalid */ private StrBuilder replaceImpl(StrMatcher matcher, String replaceStr, int from, int to, int replaceCount) { if (matcher == null || size == 0) { return this; } int replaceLen = (replaceStr == null ? 0 : replaceStr.length()); char[] buf = buffer; for (int i = from; i < to && replaceCount != 0; i++) { int removeLen = matcher.isMatch(buf, i, from, to); if (removeLen > 0) { replaceImpl(i, i + removeLen, removeLen, replaceStr, replaceLen); to = to - removeLen + replaceLen; i = i + replaceLen - 1; if (replaceCount > 0) { replaceCount--; } } } return this; } // ----------------------------------------------------------------------- /** * Reverses the string builder placing each character in the opposite index. * * @return this, to enable chaining */ public StrBuilder reverse() { if (size == 0) { return this; } int half = size / 2; char[] buf = buffer; for (int leftIdx = 0, rightIdx = size - 1; leftIdx < half; leftIdx++, rightIdx--) { char swap = buf[leftIdx]; buf[leftIdx] = buf[rightIdx]; buf[rightIdx] = swap; } return this; } // ----------------------------------------------------------------------- /** * Trims the builder by removing characters less than or equal to a space * from the beginning and end. * * @return this, to enable chaining */ public StrBuilder trim() { if (size == 0) { return this; } int len = size; char[] buf = buffer; int pos = 0; while (pos < len && buf[pos] <= ' ') { pos++; } while (pos < len && buf[len - 1] <= ' ') { len--; } if (len < size) { delete(len, size); } if (pos > 0) { delete(0, pos); } return this; } // ----------------------------------------------------------------------- /** * Checks whether this builder starts with the specified string. * <p> * Note that this method handles null input quietly, unlike String. * * @param str * the string to search for, null returns false * @return true if the builder starts with the string */ public boolean startsWith(String str) { if (str == null) { return false; } int len = str.length(); if (len == 0) { return true; } if (len > size) { return false; } for (int i = 0; i < len; i++) { if (buffer[i] != str.charAt(i)) { return false; } } return true; } /** * Checks whether this builder ends with the specified string. * <p> * Note that this method handles null input quietly, unlike String. * * @param str * the string to search for, null returns false * @return true if the builder ends with the string */ public boolean endsWith(String str) { if (str == null) { return false; } int len = str.length(); if (len == 0) { return true; } if (len > size) { return false; } int pos = size - len; for (int i = 0; i < len; i++, pos++) { if (buffer[pos] != str.charAt(i)) { return false; } } return true; } // ----------------------------------------------------------------------- /** * Extracts a portion of this string builder as a string. * * @param start * the start index, inclusive, must be valid * @return the new string * @throws IndexOutOfBoundsException * if the index is invalid */ public String substring(int start) { return substring(start, size); } /** * Extracts a portion of this string builder as a string. * <p> * Note: This method treats an endIndex greater than the length of the * builder as equal to the length of the builder, and continues without * error, unlike StringBuffer or String. * * @param startIndex * the start index, inclusive, must be valid * @param endIndex * the end index, exclusive, must be valid except that if too * large it is treated as end of string * @return the new string * @throws IndexOutOfBoundsException * if the index is invalid */ public String substring(int startIndex, int endIndex) { endIndex = validateRange(startIndex, endIndex); return new String(buffer, startIndex, endIndex - startIndex); } /** * Extracts the leftmost characters from the string builder without throwing * an exception. * <p> * This method extracts the left <code>length</code> characters from the * builder. If this many characters are not available, the whole builder is * returned. Thus the returned string may be shorter than the length * requested. * * @param length * the number of characters to extract, negative returns empty * string * @return the new string */ public String leftString(int length) { if (length <= 0) { return ""; } else if (length >= size) { return new String(buffer, 0, size); } else { return new String(buffer, 0, length); } } /** * Extracts the rightmost characters from the string builder without * throwing an exception. * <p> * This method extracts the right <code>length</code> characters from the * builder. If this many characters are not available, the whole builder is * returned. Thus the returned string may be shorter than the length * requested. * * @param length * the number of characters to extract, negative returns empty * string * @return the new string */ public String rightString(int length) { if (length <= 0) { return ""; } else if (length >= size) { return new String(buffer, 0, size); } else { return new String(buffer, size - length, length); } } /** * Extracts some characters from the middle of the string builder without * throwing an exception. * <p> * This method extracts <code>length</code> characters from the builder at * the specified index. If the index is negative it is treated as zero. If * the index is greater than the builder size, it is treated as the builder * size. If the length is negative, the empty string is returned. If * insufficient characters are available in the builder, as much as possible * is returned. Thus the returned string may be shorter than the length * requested. * * @param index * the index to start at, negative means zero * @param length * the number of characters to extract, negative returns empty * string * @return the new string */ public String midString(int index, int length) { if (index < 0) { index = 0; } if (length <= 0 || index >= size) { return ""; } if (size <= index + length) { return new String(buffer, index, size - index); } else { return new String(buffer, index, length); } } // ----------------------------------------------------------------------- /** * Checks if the string builder contains the specified char. * * @param ch * the character to find * @return true if the builder contains the character */ public boolean contains(char ch) { char[] thisBuf = buffer; for (int i = 0; i < this.size; i++) { if (thisBuf[i] == ch) { return true; } } return false; } /** * Checks if the string builder contains the specified string. * * @param str * the string to find * @return true if the builder contains the string */ public boolean contains(String str) { return indexOf(str, 0) >= 0; } /** * Checks if the string builder contains a string matched using the * specified matcher. * <p> * Matchers can be used to perform advanced searching behaviour. For example * you could write a matcher to search for the character 'a' followed by a * number. * * @param matcher * the matcher to use, null returns -1 * @return true if the matcher finds a match in the builder */ public boolean contains(StrMatcher matcher) { return indexOf(matcher, 0) >= 0; } // ----------------------------------------------------------------------- /** * Searches the string builder to find the first reference to the specified * char. * * @param ch * the character to find * @return the first index of the character, or -1 if not found */ public int indexOf(char ch) { return indexOf(ch, 0); } /** * Searches the string builder to find the first reference to the specified * char. * * @param ch * the character to find * @param startIndex * the index to start at, invalid index rounded to edge * @return the first index of the character, or -1 if not found */ public int indexOf(char ch, int startIndex) { startIndex = (startIndex < 0 ? 0 : startIndex); if (startIndex >= size) { return -1; } char[] thisBuf = buffer; for (int i = startIndex; i < size; i++) { if (thisBuf[i] == ch) { return i; } } return -1; } /** * Searches the string builder to find the first reference to the specified * string. * <p> * Note that a null input string will return -1, whereas the JDK throws an * exception. * * @param str * the string to find, null returns -1 * @return the first index of the string, or -1 if not found */ public int indexOf(String str) { return indexOf(str, 0); } /** * Searches the string builder to find the first reference to the specified * string starting searching from the given index. * <p> * Note that a null input string will return -1, whereas the JDK throws an * exception. * * @param str * the string to find, null returns -1 * @param startIndex * the index to start at, invalid index rounded to edge * @return the first index of the string, or -1 if not found */ public int indexOf(String str, int startIndex) { startIndex = (startIndex < 0 ? 0 : startIndex); if (str == null || startIndex >= size) { return -1; } int strLen = str.length(); if (strLen == 1) { return indexOf(str.charAt(0), startIndex); } if (strLen == 0) { return startIndex; } if (strLen > size) { return -1; } char[] thisBuf = buffer; int len = size - strLen + 1; outer: for (int i = startIndex; i < len; i++) { for (int j = 0; j < strLen; j++) { if (str.charAt(j) != thisBuf[i + j]) { continue outer; } } return i; } return -1; } /** * Searches the string builder using the matcher to find the first match. * <p> * Matchers can be used to perform advanced searching behaviour. For example * you could write a matcher to find the character 'a' followed by a number. * * @param matcher * the matcher to use, null returns -1 * @return the first index matched, or -1 if not found */ public int indexOf(StrMatcher matcher) { return indexOf(matcher, 0); } /** * Searches the string builder using the matcher to find the first match * searching from the given index. * <p> * Matchers can be used to perform advanced searching behaviour. For example * you could write a matcher to find the character 'a' followed by a number. * * @param matcher * the matcher to use, null returns -1 * @param startIndex * the index to start at, invalid index rounded to edge * @return the first index matched, or -1 if not found */ public int indexOf(StrMatcher matcher, int startIndex) { startIndex = (startIndex < 0 ? 0 : startIndex); if (matcher == null || startIndex >= size) { return -1; } int len = size; char[] buf = buffer; for (int i = startIndex; i < len; i++) { if (matcher.isMatch(buf, i, startIndex, len) > 0) { return i; } } return -1; } // ----------------------------------------------------------------------- /** * Searches the string builder to find the last reference to the specified * char. * * @param ch * the character to find * @return the last index of the character, or -1 if not found */ public int lastIndexOf(char ch) { return lastIndexOf(ch, size - 1); } /** * Searches the string builder to find the last reference to the specified * char. * * @param ch * the character to find * @param startIndex * the index to start at, invalid index rounded to edge * @return the last index of the character, or -1 if not found */ public int lastIndexOf(char ch, int startIndex) { startIndex = (startIndex >= size ? size - 1 : startIndex); if (startIndex < 0) { return -1; } for (int i = startIndex; i >= 0; i--) { if (buffer[i] == ch) { return i; } } return -1; } /** * Searches the string builder to find the last reference to the specified * string. * <p> * Note that a null input string will return -1, whereas the JDK throws an * exception. * * @param str * the string to find, null returns -1 * @return the last index of the string, or -1 if not found */ public int lastIndexOf(String str) { return lastIndexOf(str, size - 1); } /** * Searches the string builder to find the last reference to the specified * string starting searching from the given index. * <p> * Note that a null input string will return -1, whereas the JDK throws an * exception. * * @param str * the string to find, null returns -1 * @param startIndex * the index to start at, invalid index rounded to edge * @return the last index of the string, or -1 if not found */ public int lastIndexOf(String str, int startIndex) { startIndex = (startIndex >= size ? size - 1 : startIndex); if (str == null || startIndex < 0) { return -1; } int strLen = str.length(); if (strLen > 0 && strLen <= size) { if (strLen == 1) { return lastIndexOf(str.charAt(0), startIndex); } outer: for (int i = startIndex - strLen + 1; i >= 0; i--) { for (int j = 0; j < strLen; j++) { if (str.charAt(j) != buffer[i + j]) { continue outer; } } return i; } } else if (strLen == 0) { return startIndex; } return -1; } /** * Searches the string builder using the matcher to find the last match. * <p> * Matchers can be used to perform advanced searching behaviour. For example * you could write a matcher to find the character 'a' followed by a number. * * @param matcher * the matcher to use, null returns -1 * @return the last index matched, or -1 if not found */ public int lastIndexOf(StrMatcher matcher) { return lastIndexOf(matcher, size); } /** * Searches the string builder using the matcher to find the last match * searching from the given index. * <p> * Matchers can be used to perform advanced searching behaviour. For example * you could write a matcher to find the character 'a' followed by a number. * * @param matcher * the matcher to use, null returns -1 * @param startIndex * the index to start at, invalid index rounded to edge * @return the last index matched, or -1 if not found */ public int lastIndexOf(StrMatcher matcher, int startIndex) { startIndex = (startIndex >= size ? size - 1 : startIndex); if (matcher == null || startIndex < 0) { return -1; } char[] buf = buffer; int endIndex = startIndex + 1; for (int i = startIndex; i >= 0; i--) { if (matcher.isMatch(buf, i, 0, endIndex) > 0) { return i; } } return -1; } // ----------------------------------------------------------------------- /** * Creates a tokenizer that can tokenize the contents of this builder. * <p> * This method allows the contents of this builder to be tokenized. The * tokenizer will be setup by default to tokenize on space, tab, newline and * formfeed (as per StringTokenizer). These values can be changed on the * tokenizer class, before retrieving the tokens. * <p> * The returned tokenizer is linked to this builder. You may intermix calls * to the buider and tokenizer within certain limits, however there is no * synchronization. Once the tokenizer has been used once, it must be * {@link StrTokenizer#reset() reset} to pickup the latest changes in the * builder. For example: * * <pre> * StrBuilder b = new StrBuilder(); * b.append("a b "); * StrTokenizer t = b.asTokenizer(); * String[] tokens1 = t.getTokenArray(); // returns a,b * b.append("c d "); * String[] tokens2 = t.getTokenArray(); // returns a,b (c and d ignored) * t.reset(); // reset causes builder changes to be picked up * String[] tokens3 = t.getTokenArray(); // returns a,b,c,d * </pre> * * In addition to simply intermixing appends and tokenization, you can also * call the set methods on the tokenizer to alter how it tokenizes. Just * remember to call reset when you want to pickup builder changes. * <p> * Calling {@link StrTokenizer#reset(String)} or * {@link StrTokenizer#reset(char[])} with a non-null value will break the * link with the builder. * * @return a tokenizer that is linked to this builder */ public StrTokenizer asTokenizer() { return new StrBuilderTokenizer(); } // ----------------------------------------------------------------------- /** * Gets the contents of this builder as a Reader. * <p> * This method allows the contents of the builder to be read using any * standard method that expects a Reader. * <p> * To use, simply create a <code>StrBuilder</code>, populate it with data, * call <code>asReader</code>, and then read away. * <p> * The internal character array is shared between the builder and the * reader. This allows you to append to the builder after creating the * reader, and the changes will be picked up. Note however, that no * synchronization occurs, so you must perform all operations with the * builder and the reader in one thread. * <p> * The returned reader supports marking, and ignores the flush method. * * @return a reader that reads from this builder */ public Reader asReader() { return new StrBuilderReader(); } // ----------------------------------------------------------------------- /** * Gets this builder as a Writer that can be written to. * <p> * This method allows you to populate the contents of the builder using any * standard method that takes a Writer. * <p> * To use, simply create a <code>StrBuilder</code>, call * <code>asWriter</code>, and populate away. The data is available at any * time using the methods of the <code>StrBuilder</code>. * <p> * The internal character array is shared between the builder and the * writer. This allows you to intermix calls that append to the builder and * write using the writer and the changes will be occur correctly. Note * however, that no synchronization occurs, so you must perform all * operations with the builder and the writer in one thread. * <p> * The returned writer ignores the close and flush methods. * * @return a writer that populates this builder */ public Writer asWriter() { return new StrBuilderWriter(); } // ----------------------------------------------------------------------- // /** // * Gets a String version of the string builder by calling the internal // * constructor of String by reflection. // * <p> // * WARNING: You must not use the StrBuilder after calling this method // * as the buffer is now shared with the String object. To ensure this, // * the internal character array is set to null, so you will get // * NullPointerExceptions on all method calls. // * // * @return the builder as a String // */ // public String toSharedString() { // try { // Constructor con = String.class.getDeclaredConstructor( // new Class[] {int.class, int.class, char[].class}); // con.setAccessible(true); // char[] buffer = buf; // buf = null; // size = -1; // nullText = null; // return (String) con.newInstance( // new Object[] {new Integer(0), new Integer(size), buffer}); // // } catch (Exception ex) { // ex.printStackTrace(); // throw new // UnsupportedOperationException("StrBuilder.toSharedString is unsupported: " // + ex.getMessage()); // } // } // ----------------------------------------------------------------------- /** * Checks the contents of this builder against another to see if they * contain the same character content ignoring case. * * @param other * the object to check, null returns false * @return true if the builders contain the same characters in the same * order */ public boolean equalsIgnoreCase(StrBuilder other) { if (this == other) { return true; } if (this.size != other.size) { return false; } char thisBuf[] = this.buffer; char otherBuf[] = other.buffer; for (int i = size - 1; i >= 0; i--) { char c1 = thisBuf[i]; char c2 = otherBuf[i]; if (c1 != c2 && Character.toUpperCase(c1) != Character.toUpperCase(c2)) { return false; } } return true; } /** * Checks the contents of this builder against another to see if they * contain the same character content. * * @param other * the object to check, null returns false * @return true if the builders contain the same characters in the same * order */ public boolean equals(StrBuilder other) { if (this == other) { return true; } if (this.size != other.size) { return false; } char thisBuf[] = this.buffer; char otherBuf[] = other.buffer; for (int i = size - 1; i >= 0; i--) { if (thisBuf[i] != otherBuf[i]) { return false; } } return true; } /** * Checks the contents of this builder against another to see if they * contain the same character content. * * @param obj * the object to check, null returns false * @return true if the builders contain the same characters in the same * order */ public boolean equals(Object obj) { if (obj instanceof StrBuilder) { return equals((StrBuilder) obj); } return false; } /** * Gets a suitable hash code for this builder. * * @return a hash code */ public int hashCode() { char buf[] = buffer; int hash = 0; for (int i = size - 1; i >= 0; i--) { hash = 31 * hash + buf[i]; } return hash; } // ----------------------------------------------------------------------- /** * Gets a String version of the string builder, creating a new instance each * time the method is called. * <p> * Note that unlike StringBuffer, the string version returned is independent * of the string builder. * * @return the builder as a String */ public String toString() { return new String(buffer, 0, size); } /** * Gets a StringBuffer version of the string builder, creating a new * instance each time the method is called. * * @return the builder as a StringBuffer */ public StringBuffer toStringBuffer() { return new StringBuffer(size).append(buffer, 0, size); } /** * Clone this object. * * @return a clone of this object * @throws CloneNotSupportedException * if clone is not supported * @since 2.6 */ public Object clone() throws CloneNotSupportedException { StrBuilder clone = (StrBuilder) super.clone(); clone.buffer = new char[buffer.length]; System.arraycopy(buffer, 0, clone.buffer, 0, buffer.length); return clone; } // ----------------------------------------------------------------------- /** * Validates parameters defining a range of the builder. * * @param startIndex * the start index, inclusive, must be valid * @param endIndex * the end index, exclusive, must be valid except that if too * large it is treated as end of string * @return the new string * @throws IndexOutOfBoundsException * if the index is invalid */ protected int validateRange(int startIndex, int endIndex) { if (startIndex < 0) { throw new StringIndexOutOfBoundsException(startIndex); } if (endIndex > size) { endIndex = size; } if (startIndex > endIndex) { throw new StringIndexOutOfBoundsException("end < start"); } return endIndex; } /** * Validates parameters defining a single index in the builder. * * @param index * the index, must be valid * @throws IndexOutOfBoundsException * if the index is invalid */ protected void validateIndex(int index) { if (index < 0 || index > size) { throw new StringIndexOutOfBoundsException(index); } } // ----------------------------------------------------------------------- /** * Inner class to allow StrBuilder to operate as a tokenizer. */ class StrBuilderTokenizer extends StrTokenizer { /** * Default constructor. */ StrBuilderTokenizer() { super(); } /** {@inheritDoc} */ protected List<String> tokenize(char[] chars, int offset, int count) { if (chars == null) { return super.tokenize(StrBuilder.this.buffer, 0, StrBuilder.this.size()); } else { return super.tokenize(chars, offset, count); } } /** {@inheritDoc} */ public String getContent() { String str = super.getContent(); if (str == null) { return StrBuilder.this.toString(); } else { return str; } } } // ----------------------------------------------------------------------- /** * Inner class to allow StrBuilder to operate as a writer. */ class StrBuilderReader extends Reader { /** The current stream position. */ private int pos; /** The last mark position. */ private int mark; /** * Default constructor. */ StrBuilderReader() { super(); } /** {@inheritDoc} */ public void close() { // do nothing } /** {@inheritDoc} */ public int read() { if (ready() == false) { return -1; } return StrBuilder.this.charAt(pos++); } /** {@inheritDoc} */ public int read(char b[], int off, int len) { if (off < 0 || len < 0 || off > b.length || (off + len) > b.length || (off + len) < 0) { throw new IndexOutOfBoundsException(); } if (len == 0) { return 0; } if (pos >= StrBuilder.this.size()) { return -1; } if (pos + len > size()) { len = StrBuilder.this.size() - pos; } StrBuilder.this.getChars(pos, pos + len, b, off); pos += len; return len; } /** {@inheritDoc} */ public long skip(long n) { if (pos + n > StrBuilder.this.size()) { n = StrBuilder.this.size() - pos; } if (n < 0) { return 0; } pos += n; return n; } /** {@inheritDoc} */ public boolean ready() { return pos < StrBuilder.this.size(); } /** {@inheritDoc} */ public boolean markSupported() { return true; } /** {@inheritDoc} */ public void mark(int readAheadLimit) { mark = pos; } /** {@inheritDoc} */ public void reset() { pos = mark; } } // ----------------------------------------------------------------------- /** * Inner class to allow StrBuilder to operate as a writer. */ class StrBuilderWriter extends Writer { /** * Default constructor. */ StrBuilderWriter() { super(); } /** {@inheritDoc} */ public void close() { // do nothing } /** {@inheritDoc} */ public void flush() { // do nothing } /** {@inheritDoc} */ public void write(int c) { StrBuilder.this.append((char) c); } /** {@inheritDoc} */ public void write(char[] cbuf) { StrBuilder.this.append(cbuf); } /** {@inheritDoc} */ public void write(char[] cbuf, int off, int len) { StrBuilder.this.append(cbuf, off, len); } /** {@inheritDoc} */ public void write(String str) { StrBuilder.this.append(str); } /** {@inheritDoc} */ public void write(String str, int off, int len) { StrBuilder.this.append(str, off, len); } } }