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/* * Copyright (c) 2000, 2005, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ // AttributesImpl.java - default implementation of Attributes. // http://www.saxproject.org // Written by David Megginson // NO WARRANTY! This class is in the public domain. // $Id: AttributesImpl.java,v 1.2 2004/11/03 22:53:08 jsuttor Exp $ package org.xml.sax.helpers; import org.xml.sax.Attributes; /** * Default implementation of the Attributes interface. * * <blockquote> * <em>This module, both source code and documentation, is in the * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em> * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a> * for further information. * </blockquote> * * <p>This class provides a default implementation of the SAX2 * {@link org.xml.sax.Attributes Attributes} interface, with the * addition of manipulators so that the list can be modified or * reused.</p> * * <p>There are two typical uses of this class:</p> * * <ol> * <li>to take a persistent snapshot of an Attributes object * in a {@link org.xml.sax.ContentHandler#startElement startElement} event; or</li> * <li>to construct or modify an Attributes object in a SAX2 driver or filter.</li> * </ol> * * <p>This class replaces the now-deprecated SAX1 {@link * org.xml.sax.helpers.AttributeListImpl AttributeListImpl} * class; in addition to supporting the updated Attributes * interface rather than the deprecated {@link org.xml.sax.AttributeList * AttributeList} interface, it also includes a much more efficient * implementation using a single array rather than a set of Vectors.</p> * * @since 1.4, SAX 2.0 * @author David Megginson */ public class AttributesImpl implements Attributes { //////////////////////////////////////////////////////////////////// // Constructors. //////////////////////////////////////////////////////////////////// /** * Construct a new, empty AttributesImpl object. */ public AttributesImpl() { length = 0; data = null; } /** * Copy an existing Attributes object. * * <p>This constructor is especially useful inside a * {@link org.xml.sax.ContentHandler#startElement startElement} event.</p> * * @param atts The existing Attributes object. */ public AttributesImpl(Attributes atts) { setAttributes(atts); } //////////////////////////////////////////////////////////////////// // Implementation of org.xml.sax.Attributes. //////////////////////////////////////////////////////////////////// /** * Return the number of attributes in the list. * * @return The number of attributes in the list. * @see org.xml.sax.Attributes#getLength */ public int getLength() { return length; } /** * Return an attribute's Namespace URI. * * @param index The attribute's index (zero-based). * @return The Namespace URI, the empty string if none is * available, or null if the index is out of range. * @see org.xml.sax.Attributes#getURI */ public String getURI(int index) { if (index >= 0 && index < length) { return data[index * 5]; } else { return null; } } /** * Return an attribute's local name. * * @param index The attribute's index (zero-based). * @return The attribute's local name, the empty string if * none is available, or null if the index if out of range. * @see org.xml.sax.Attributes#getLocalName */ public String getLocalName(int index) { if (index >= 0 && index < length) { return data[index * 5 + 1]; } else { return null; } } /** * Return an attribute's qualified (prefixed) name. * * @param index The attribute's index (zero-based). * @return The attribute's qualified name, the empty string if * none is available, or null if the index is out of bounds. * @see org.xml.sax.Attributes#getQName */ public String getQName(int index) { if (index >= 0 && index < length) { return data[index * 5 + 2]; } else { return null; } } /** * Return an attribute's type by index. * * @param index The attribute's index (zero-based). * @return The attribute's type, "CDATA" if the type is unknown, or null * if the index is out of bounds. * @see org.xml.sax.Attributes#getType(int) */ public String getType(int index) { if (index >= 0 && index < length) { return data[index * 5 + 3]; } else { return null; } } /** * Return an attribute's value by index. * * @param index The attribute's index (zero-based). * @return The attribute's value or null if the index is out of bounds. * @see org.xml.sax.Attributes#getValue(int) */ public String getValue(int index) { if (index >= 0 && index < length) { return data[index * 5 + 4]; } else { return null; } } /** * Look up an attribute's index by Namespace name. * * <p>In many cases, it will be more efficient to look up the name once and * use the index query methods rather than using the name query methods * repeatedly.</p> * * @param uri The attribute's Namespace URI, or the empty * string if none is available. * @param localName The attribute's local name. * @return The attribute's index, or -1 if none matches. * @see org.xml.sax.Attributes#getIndex(java.lang.String,java.lang.String) */ public int getIndex(String uri, String localName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i].equals(uri) && data[i + 1].equals(localName)) { return i / 5; } } return -1; } /** * Look up an attribute's index by qualified (prefixed) name. * * @param qName The qualified name. * @return The attribute's index, or -1 if none matches. * @see org.xml.sax.Attributes#getIndex(java.lang.String) */ public int getIndex(String qName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i + 2].equals(qName)) { return i / 5; } } return -1; } /** * Look up an attribute's type by Namespace-qualified name. * * @param uri The Namespace URI, or the empty string for a name * with no explicit Namespace URI. * @param localName The local name. * @return The attribute's type, or null if there is no * matching attribute. * @see org.xml.sax.Attributes#getType(java.lang.String,java.lang.String) */ public String getType(String uri, String localName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i].equals(uri) && data[i + 1].equals(localName)) { return data[i + 3]; } } return null; } /** * Look up an attribute's type by qualified (prefixed) name. * * @param qName The qualified name. * @return The attribute's type, or null if there is no * matching attribute. * @see org.xml.sax.Attributes#getType(java.lang.String) */ public String getType(String qName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i + 2].equals(qName)) { return data[i + 3]; } } return null; } /** * Look up an attribute's value by Namespace-qualified name. * * @param uri The Namespace URI, or the empty string for a name * with no explicit Namespace URI. * @param localName The local name. * @return The attribute's value, or null if there is no * matching attribute. * @see org.xml.sax.Attributes#getValue(java.lang.String,java.lang.String) */ public String getValue(String uri, String localName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i].equals(uri) && data[i + 1].equals(localName)) { return data[i + 4]; } } return null; } /** * Look up an attribute's value by qualified (prefixed) name. * * @param qName The qualified name. * @return The attribute's value, or null if there is no * matching attribute. * @see org.xml.sax.Attributes#getValue(java.lang.String) */ public String getValue(String qName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i + 2].equals(qName)) { return data[i + 4]; } } return null; } //////////////////////////////////////////////////////////////////// // Manipulators. //////////////////////////////////////////////////////////////////// /** * Clear the attribute list for reuse. * * <p>Note that little memory is freed by this call: * the current array is kept so it can be * reused.</p> */ public void clear() { if (data != null) { for (int i = 0; i < (length * 5); i++) data[i] = null; } length = 0; } /** * Copy an entire Attributes object. * * <p>It may be more efficient to reuse an existing object * rather than constantly allocating new ones.</p> * * @param atts The attributes to copy. */ public void setAttributes(Attributes atts) { clear(); length = atts.getLength(); if (length > 0) { data = new String[length * 5]; for (int i = 0; i < length; i++) { data[i * 5] = atts.getURI(i); data[i * 5 + 1] = atts.getLocalName(i); data[i * 5 + 2] = atts.getQName(i); data[i * 5 + 3] = atts.getType(i); data[i * 5 + 4] = atts.getValue(i); } } } /** * Add an attribute to the end of the list. * * <p>For the sake of speed, this method does no checking * to see if the attribute is already in the list: that is * the responsibility of the application.</p> * * @param uri The Namespace URI, or the empty string if * none is available or Namespace processing is not * being performed. * @param localName The local name, or the empty string if * Namespace processing is not being performed. * @param qName The qualified (prefixed) name, or the empty string * if qualified names are not available. * @param type The attribute type as a string. * @param value The attribute value. */ public void addAttribute(String uri, String localName, String qName, String type, String value) { ensureCapacity(length + 1); data[length * 5] = uri; data[length * 5 + 1] = localName; data[length * 5 + 2] = qName; data[length * 5 + 3] = type; data[length * 5 + 4] = value; length++; } /** * Set an attribute in the list. * * <p>For the sake of speed, this method does no checking * for name conflicts or well-formedness: such checks are the * responsibility of the application.</p> * * @param index The index of the attribute (zero-based). * @param uri The Namespace URI, or the empty string if * none is available or Namespace processing is not * being performed. * @param localName The local name, or the empty string if * Namespace processing is not being performed. * @param qName The qualified name, or the empty string * if qualified names are not available. * @param type The attribute type as a string. * @param value The attribute value. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */ public void setAttribute(int index, String uri, String localName, String qName, String type, String value) { if (index >= 0 && index < length) { data[index * 5] = uri; data[index * 5 + 1] = localName; data[index * 5 + 2] = qName; data[index * 5 + 3] = type; data[index * 5 + 4] = value; } else { badIndex(index); } } /** * Remove an attribute from the list. * * @param index The index of the attribute (zero-based). * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */ public void removeAttribute(int index) { if (index >= 0 && index < length) { if (index < length - 1) { System.arraycopy(data, (index + 1) * 5, data, index * 5, (length - index - 1) * 5); } index = (length - 1) * 5; data[index++] = null; data[index++] = null; data[index++] = null; data[index++] = null; data[index] = null; length--; } else { badIndex(index); } } /** * Set the Namespace URI of a specific attribute. * * @param index The index of the attribute (zero-based). * @param uri The attribute's Namespace URI, or the empty * string for none. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */ public void setURI(int index, String uri) { if (index >= 0 && index < length) { data[index * 5] = uri; } else { badIndex(index); } } /** * Set the local name of a specific attribute. * * @param index The index of the attribute (zero-based). * @param localName The attribute's local name, or the empty * string for none. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */ public void setLocalName(int index, String localName) { if (index >= 0 && index < length) { data[index * 5 + 1] = localName; } else { badIndex(index); } } /** * Set the qualified name of a specific attribute. * * @param index The index of the attribute (zero-based). * @param qName The attribute's qualified name, or the empty * string for none. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */ public void setQName(int index, String qName) { if (index >= 0 && index < length) { data[index * 5 + 2] = qName; } else { badIndex(index); } } /** * Set the type of a specific attribute. * * @param index The index of the attribute (zero-based). * @param type The attribute's type. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */ public void setType(int index, String type) { if (index >= 0 && index < length) { data[index * 5 + 3] = type; } else { badIndex(index); } } /** * Set the value of a specific attribute. * * @param index The index of the attribute (zero-based). * @param value The attribute's value. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */ public void setValue(int index, String value) { if (index >= 0 && index < length) { data[index * 5 + 4] = value; } else { badIndex(index); } } //////////////////////////////////////////////////////////////////// // Internal methods. //////////////////////////////////////////////////////////////////// /** * Ensure the internal array's capacity. * * @param n The minimum number of attributes that the array must * be able to hold. */ private void ensureCapacity(int n) { if (n <= 0) { return; } int max; if (data == null || data.length == 0) { max = 25; } else if (data.length >= n * 5) { return; } else { max = data.length; } while (max < n * 5) { max *= 2; } String newData[] = new String[max]; if (length > 0) { System.arraycopy(data, 0, newData, 0, length * 5); } data = newData; } /** * Report a bad array index in a manipulator. * * @param index The index to report. * @exception java.lang.ArrayIndexOutOfBoundsException Always. */ private void badIndex(int index) throws ArrayIndexOutOfBoundsException { String msg = "Attempt to modify attribute at illegal index: " + index; throw new ArrayIndexOutOfBoundsException(msg); } //////////////////////////////////////////////////////////////////// // Internal state. //////////////////////////////////////////////////////////////////// int length; String data[]; } // end of AttributesImpl.java