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/* * 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. * * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation and was * originally based on software copyright (c) 1999, International * Business Machines, Inc., http://www.apache.org. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. */ /** * XMLString is a structure used to pass character arrays. However, * XMLStringBuffer is a buffer in which characters can be appended * and extends XMLString so that it can be passed to methods * expecting an XMLString object. This is a safe operation because * it is assumed that any callee will <strong>not</strong> modify * the contents of the XMLString structure. * <p> * The contents of the string are managed by the string buffer. As * characters are appended, the string buffer will grow as needed. * <p> * <strong>Note:</strong> Never set the <code>ch</code>, * <code>offset</code>, and <code>length</code> fields directly. * These fields are managed by the string buffer. In order to reset * the buffer, call <code>clear()</code>. * * @author Andy Clark, IBM * @author Eric Ye, IBM * * @version $Id: XMLStringBuffer.java 515 2008-03-17 21:02:23Z jfrederic.clere@jboss.com $ */ public class XMLStringBuffer extends XMLString { // // Constants // /** Default buffer size (32). */ public static final int DEFAULT_SIZE = 32; // // Constructors // /** * */ public XMLStringBuffer() { this(DEFAULT_SIZE); } // <init>() /** * * * @param size */ public XMLStringBuffer(int size) { ch = new char[size]; } // <init>(int) /** Constructs a string buffer from a char. */ public XMLStringBuffer(char c) { this(1); append(c); } // <init>(char) /** Constructs a string buffer from a String. */ public XMLStringBuffer(String s) { this(s.length()); append(s); } // <init>(String) /** Constructs a string buffer from the specified character array. */ public XMLStringBuffer(char[] ch, int offset, int length) { this(length); append(ch, offset, length); } // <init>(char[],int,int) /** Constructs a string buffer from the specified XMLString. */ public XMLStringBuffer(XMLString s) { this(s.length); append(s); } // <init>(XMLString) // // Public methods // /** Clears the string buffer. */ public void clear() { offset = 0; length = 0; } /** * append * * @param c */ public void append(char c) { if (this.length + 1 > this.ch.length) { int newLength = this.ch.length * 2; if (newLength < this.ch.length + DEFAULT_SIZE) newLength = this.ch.length + DEFAULT_SIZE; char[] newch = new char[newLength]; System.arraycopy(this.ch, 0, newch, 0, this.length); this.ch = newch; } this.ch[this.length] = c; this.length++; } // append(char) /** * append * * @param s */ public void append(String s) { int length = s.length(); if (this.length + length > this.ch.length) { int newLength = this.ch.length * 2; if (newLength < this.length + length + DEFAULT_SIZE) newLength = this.ch.length + length + DEFAULT_SIZE; char[] newch = new char[newLength]; System.arraycopy(this.ch, 0, newch, 0, this.length); this.ch = newch; } s.getChars(0, length, this.ch, this.length); this.length += length; } // append(String) /** * append * * @param ch * @param offset * @param length */ public void append(char[] ch, int offset, int length) { if (this.length + length > this.ch.length) { char[] newch = new char[this.ch.length + length + DEFAULT_SIZE]; System.arraycopy(this.ch, 0, newch, 0, this.length); this.ch = newch; } System.arraycopy(ch, offset, this.ch, this.length, length); this.length += length; } // append(char[],int,int) /** * append * * @param s */ public void append(XMLString s) { append(s.ch, s.offset, s.length); } // append(XMLString) } // class XMLStringBuffer /* * 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. * * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation and was * originally based on software copyright (c) 1999, International * Business Machines, Inc., http://www.apache.org. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. */ /** * This class is used as a structure to pass text contained in the underlying * character buffer of the scanner. The offset and length fields allow the * buffer to be re-used without creating new character arrays. * <p> * <strong>Note:</strong> Methods that are passed an XMLString structure * should consider the contents read-only and not make any modifications * to the contents of the buffer. The method receiving this structure * should also not modify the offset and length if this structure (or * the values of this structure) are passed to another method. * <p> * <strong>Note:</strong> Methods that are passed an XMLString structure * are required to copy the information out of the buffer if it is to be * saved for use beyond the scope of the method. The contents of the * structure are volatile and the contents of the character buffer cannot * be assured once the method that is passed this structure returns. * Therefore, methods passed this structure should not save any reference * to the structure or the character array contained in the structure. * * @author Eric Ye, IBM * @author Andy Clark, IBM * * @version $Id: XMLString.java 515 2008-03-17 21:02:23Z jfrederic.clere@jboss.com $ */ class XMLString { // // Data // /** The character array. */ public char[] ch; /** The offset into the character array. */ public int offset; /** The length of characters from the offset. */ public int length; // // Constructors // /** Default constructor. */ public XMLString() { } // <init>() /** * Constructs an XMLString structure preset with the specified * values. * * @param ch The character array. * @param offset The offset into the character array. * @param length The length of characters from the offset. */ public XMLString(char[] ch, int offset, int length) { setValues(ch, offset, length); } // <init>(char[],int,int) /** * Constructs an XMLString structure with copies of the values in * the given structure. * <p> * <strong>Note:</strong> This does not copy the character array; * only the reference to the array is copied. * * @param string The XMLString to copy. */ public XMLString(XMLString string) { setValues(string); } // <init>(XMLString) // // Public methods // /** * Initializes the contents of the XMLString structure with the * specified values. * * @param ch The character array. * @param offset The offset into the character array. * @param length The length of characters from the offset. */ public void setValues(char[] ch, int offset, int length) { this.ch = ch; this.offset = offset; this.length = length; } // setValues(char[],int,int) /** * Initializes the contents of the XMLString structure with copies * of the given string structure. * <p> * <strong>Note:</strong> This does not copy the character array; * only the reference to the array is copied. * * @param s */ public void setValues(XMLString s) { setValues(s.ch, s.offset, s.length); } // setValues(XMLString) /** Resets all of the values to their defaults. */ public void clear() { this.ch = null; this.offset = 0; this.length = -1; } // clear() /** * Returns true if the contents of this XMLString structure and * the specified array are equal. * * @param ch The character array. * @param offset The offset into the character array. * @param length The length of characters from the offset. */ public boolean equals(char[] ch, int offset, int length) { if (ch == null) { return false; } if (this.length != length) { return false; } for (int i = 0; i < length; i++) { if (this.ch[this.offset + i] != ch[offset + i]) { return false; } } return true; } // equals(char[],int,int):boolean /** * Returns true if the contents of this XMLString structure and * the specified string are equal. * * @param s The string to compare. */ public boolean equals(String s) { if (s == null) { return false; } if (length != s.length()) { return false; } // is this faster than call s.toCharArray first and compare the // two arrays directly, which will possibly involve creating a // new char array object. for (int i = 0; i < length; i++) { if (ch[offset + i] != s.charAt(i)) { return false; } } return true; } // equals(String):boolean // // Object methods // /** Returns a string representation of this object. */ public String toString() { return length > 0 ? new String(ch, offset, length) : ""; } // toString():String } // class XMLString