001: /*****************************************************************************
002: * Source code information
003: * -----------------------
004: * Original author Ian Dickinson, HP Labs Bristol
005: * Author email ian.dickinson@hp.com
006: * Package Jena 2
007: * Web http://sourceforge.net/projects/jena/
008: * Created 04-Dec-2003
009: * Filename $RCSfile: SimpleXMLPathElement.java,v $
010: * Revision $Revision: 1.8 $
011: * Release status $State: Exp $
012: *
013: * Last modified on $Date: 2008/01/02 12:09:42 $
014: * by $Author: andy_seaborne $
015: *
016: * (c) Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Hewlett-Packard Development Company, LP
017: * [See end of file]
018: *****************************************************************************/package com.hp.hpl.jena.util.xml;
019:
020: // Imports
021: ///////////////
022: import java.util.*;
023:
024: import org.w3c.dom.*;
025:
026: /**
027: * <p>
028: * An implementation of a simple XML path component that handles named elements.
029: * </p>
030: *
031: * @author Ian Dickinson, HP Labs (<a href="mailto:Ian.Dickinson@hp.com" >email</a>)
032: * @version CVS $Id: SimpleXMLPathElement.java,v 1.8 2008/01/02 12:09:42 andy_seaborne Exp $
033: */
034: public class SimpleXMLPathElement implements SimpleXMLPathComponent {
035: // Constants
036: //////////////////////////////////
037:
038: /** Constant to select all children of a node */
039: public static final String ALL_CHILDREN = "*";
040:
041: // Static variables
042: //////////////////////////////////
043:
044: // Instance variables
045: //////////////////////////////////
046:
047: /** The element name we are evaluating */
048: protected String m_elemName;
049:
050: // Constructors
051: //////////////////////////////////
052:
053: /**
054: * <p>Construct a simple XML path component that selects a named
055: * element from the parent.</p>
056: * @param elemName The name of the element to extract
057: */
058: public SimpleXMLPathElement(String elemName) {
059: m_elemName = elemName;
060: }
061:
062: /**
063: * <p>Construct a simple XML path component that selects all child
064: * elements of the parent node.</p>
065: */
066: public SimpleXMLPathElement() {
067: m_elemName = ALL_CHILDREN;
068: }
069:
070: // External signature methods
071: //////////////////////////////////
072:
073: /**
074: * <p>Answer an iterator over all of the values of this path component when
075: * evaluated with respect to the given node.</p>
076: * @param node The parent node to evaluate against
077: * @return An iterator over all of the objects that correspond to evaluating
078: * this path against the given node.
079: */
080: public Iterator getAll(Node node) {
081: // elements should occur within elements
082: if (!(node instanceof Element)) {
083: throw new IllegalArgumentException("Tried to get element "
084: + m_elemName + " from a parent node of type "
085: + node.getClass().getName());
086: }
087:
088: return new NodeListIterator(((Element) node)
089: .getElementsByTagName(m_elemName));
090: }
091:
092: /**
093: * <p>Answer the first value for this path expression against the given node.</p>
094: * @param node The parent node to evalauate against
095: * @return The first object that corresponds to evaluating
096: * this path against the given node, or null if there is no such value
097: */
098: public Object getFirst(Node node) {
099: return getAll(node).next();
100: }
101:
102: // Internal implementation methods
103: //////////////////////////////////
104:
105: //==============================================================================
106: // Inner class definitions
107: //==============================================================================
108:
109: }
110:
111: /*
112: * (c) Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Hewlett-Packard Development Company, LP
113: * All rights reserved.
114: *
115: * Redistribution and use in source and binary forms, with or without
116: * modification, are permitted provided that the following conditions
117: * are met:
118: * 1. Redistributions of source code must retain the above copyright
119: * notice, this list of conditions and the following disclaimer.
120: * 2. Redistributions in binary form must reproduce the above copyright
121: * notice, this list of conditions and the following disclaimer in the
122: * documentation and/or other materials provided with the distribution.
123: * 3. The name of the author may not be used to endorse or promote products
124: * derived from this software without specific prior written permission.
125: *
126: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
127: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
128: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
129: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
130: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
131: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
132: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
133: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
134: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
135: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
136: */
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