1/*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the  "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 *     http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18// $Id: XPathFactoryImpl.java 468655 2006-10-28 07:12:06Z minchau $
19
20package org.apache.xpath.jaxp;
21
22import org.apache.xpath.res.XPATHErrorResources;
23import org.apache.xalan.res.XSLMessages;
24
25import javax.xml.XMLConstants;
26import javax.xml.xpath.XPathFactory;
27import javax.xml.xpath.XPathFactoryConfigurationException;
28import javax.xml.xpath.XPathFunctionResolver;
29import javax.xml.xpath.XPathVariableResolver;
30
31/**
32 * The XPathFactory builds XPaths.
33 *
34 * @version $Revision: 468655 $
35 * @author  Ramesh Mandava
36 */
37public  class XPathFactoryImpl extends XPathFactory {
38
39	/**
40	 * <p>Name of class as a constant to use for debugging.</p>
41	 */
42	private static final String CLASS_NAME = "XPathFactoryImpl";
43
44	/**
45	 *<p>XPathFunctionResolver for this XPathFactory and created XPaths.</p>
46	 */
47	private XPathFunctionResolver xPathFunctionResolver = null;
48
49	/**
50	 * <p>XPathVariableResolver for this XPathFactory and created XPaths</p>
51	 */
52	private XPathVariableResolver xPathVariableResolver = null;
53
54	/**
55	 * <p>State of secure processing feature.</p>
56	 */
57	private boolean featureSecureProcessing = false;
58
59	/**
60	 * <p>Is specified object model supported by this
61         * <code>XPathFactory</code>?</p>
62	 *
63	 * @param objectModel Specifies the object model which the returned
64         * <code>XPathFactory</code> will understand.
65	 *
66	 * @return <code>true</code> if <code>XPathFactory</code> supports
67         * <code>objectModel</code>, else <code>false</code>.
68	 *
69	 * @throws NullPointerException If <code>objectModel</code> is <code>null</code>.
70	 * @throws IllegalArgumentException If <code>objectModel.length() == 0</code>.
71	 */
72	public boolean isObjectModelSupported(String objectModel) {
73
74            if (objectModel == null) {
75                String fmsg = XSLMessages.createXPATHMessage(
76                        XPATHErrorResources.ER_OBJECT_MODEL_NULL,
77                        new Object[] { this.getClass().getName() } );
78
79                throw new NullPointerException( fmsg );
80            }
81
82            if (objectModel.length() == 0) {
83                String fmsg = XSLMessages.createXPATHMessage(
84                        XPATHErrorResources.ER_OBJECT_MODEL_EMPTY,
85                        new Object[] { this.getClass().getName() } );
86                throw new IllegalArgumentException( fmsg );
87            }
88
89	    // know how to support default object model, W3C DOM
90            if (objectModel.equals(XPathFactory.DEFAULT_OBJECT_MODEL_URI)) {
91                return true;
92            }
93
94            // don't know how to support anything else
95            return false;
96	}
97
98        /**
99         * <p>Returns a new <code>XPath</code> object using the underlying
100         * object model determined when the factory was instantiated.</p>
101	 *
102	 * @return New <code>XPath</code>
103	 */
104	public javax.xml.xpath.XPath newXPath() {
105	    return new org.apache.xpath.jaxp.XPathImpl(
106                    xPathVariableResolver, xPathFunctionResolver,
107                    featureSecureProcessing );
108	}
109
110	/**
111	 * <p>Set a feature for this <code>XPathFactory</code> and
112         * <code>XPath</code>s created by this factory.</p>
113	 *
114	 * <p>
115	 * Feature names are fully qualified {@link java.net.URI}s.
116	 * Implementations may define their own features.
117	 * An {@link XPathFactoryConfigurationException} is thrown if this
118         * <code>XPathFactory</code> or the <code>XPath</code>s
119	 *  it creates cannot support the feature.
120	 * It is possible for an <code>XPathFactory</code> to expose a feature
121         * value but be unable to change its state.
122	 * </p>
123	 *
124	 * <p>See {@link javax.xml.xpath.XPathFactory} for full documentation
125         * of specific features.</p>
126	 *
127	 * @param name Feature name.
128	 * @param value Is feature state <code>true</code> or <code>false</code>.
129	 *
130	 * @throws XPathFactoryConfigurationException if this
131         * <code>XPathFactory</code> or the <code>XPath</code>s
132	 *   it creates cannot support this feature.
133         * @throws NullPointerException if <code>name</code> is
134         * <code>null</code>.
135	 */
136	public void setFeature(String name, boolean value)
137		throws XPathFactoryConfigurationException {
138
139            // feature name cannot be null
140            if (name == null) {
141                String fmsg = XSLMessages.createXPATHMessage(
142                        XPATHErrorResources.ER_FEATURE_NAME_NULL,
143                        new Object[] { CLASS_NAME, new Boolean( value) } );
144                throw new NullPointerException( fmsg );
145             }
146
147            // secure processing?
148            if (name.equals(XMLConstants.FEATURE_SECURE_PROCESSING)) {
149
150                featureSecureProcessing = value;
151
152                // all done processing feature
153                return;
154            }
155
156            // unknown feature
157            String fmsg = XSLMessages.createXPATHMessage(
158                    XPATHErrorResources.ER_FEATURE_UNKNOWN,
159                    new Object[] { name, CLASS_NAME, new Boolean(value) } );
160            throw new XPathFactoryConfigurationException( fmsg );
161	}
162
163	/**
164	 * <p>Get the state of the named feature.</p>
165	 *
166	 * <p>
167	 * Feature names are fully qualified {@link java.net.URI}s.
168	 * Implementations may define their own features.
169	 * An {@link XPathFactoryConfigurationException} is thrown if this
170         * <code>XPathFactory</code> or the <code>XPath</code>s
171	 * it creates cannot support the feature.
172	 * It is possible for an <code>XPathFactory</code> to expose a feature
173         * value but be unable to change its state.
174	 * </p>
175	 *
176	 * @param name Feature name.
177	 *
178	 * @return State of the named feature.
179	 *
180	 * @throws XPathFactoryConfigurationException if this
181         * <code>XPathFactory</code> or the <code>XPath</code>s
182	 *   it creates cannot support this feature.
183         * @throws NullPointerException if <code>name</code> is
184         * <code>null</code>.
185	 */
186	public boolean getFeature(String name)
187		throws XPathFactoryConfigurationException {
188
189            // feature name cannot be null
190            if (name == null) {
191                String fmsg = XSLMessages.createXPATHMessage(
192                        XPATHErrorResources.ER_GETTING_NULL_FEATURE,
193                        new Object[] { CLASS_NAME } );
194                throw new NullPointerException( fmsg );
195            }
196
197            // secure processing?
198            if (name.equals(XMLConstants.FEATURE_SECURE_PROCESSING)) {
199                return featureSecureProcessing;
200            }
201
202            // unknown feature
203            String fmsg = XSLMessages.createXPATHMessage(
204                    XPATHErrorResources.ER_GETTING_UNKNOWN_FEATURE,
205                    new Object[] { name, CLASS_NAME } );
206
207            throw new XPathFactoryConfigurationException( fmsg );
208        }
209
210	/**
211         * <p>Establish a default function resolver.</p>
212         *
213	 * <p>Any <code>XPath</code> objects constructed from this factory will use
214	 * the specified resolver by default.</p>
215	 *
216	 * <p>A <code>NullPointerException</code> is thrown if
217         * <code>resolver</code> is <code>null</code>.</p>
218         *
219	 * @param resolver XPath function resolver.
220	 *
221	 * @throws NullPointerException If <code>resolver</code> is
222         * <code>null</code>.
223	 */
224        public void setXPathFunctionResolver(XPathFunctionResolver resolver) {
225
226            // resolver cannot be null
227            if (resolver == null) {
228                String fmsg = XSLMessages.createXPATHMessage(
229                        XPATHErrorResources.ER_NULL_XPATH_FUNCTION_RESOLVER,
230                        new Object[] {  CLASS_NAME } );
231                throw new NullPointerException( fmsg );
232            }
233
234            xPathFunctionResolver = resolver;
235        }
236
237	/**
238	 * <p>Establish a default variable resolver.</p>
239	 *
240	 * <p>Any <code>XPath</code> objects constructed from this factory will use
241	 * the specified resolver by default.</p>
242	 *
243	 * <p>A <code>NullPointerException</code> is thrown if <code>resolver</code> is <code>null</code>.</p>
244	 *
245	 * @param resolver Variable resolver.
246	 *
247	 *  @throws NullPointerException If <code>resolver</code> is
248         * <code>null</code>.
249	 */
250	public void setXPathVariableResolver(XPathVariableResolver resolver) {
251
252		// resolver cannot be null
253		if (resolver == null) {
254                    String fmsg = XSLMessages.createXPATHMessage(
255                            XPATHErrorResources.ER_NULL_XPATH_VARIABLE_RESOLVER,
256                            new Object[] {  CLASS_NAME } );
257		    throw new NullPointerException( fmsg );
258		}
259
260		xPathVariableResolver = resolver;
261	}
262}
263
264
265
266