1 /*
2 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.org.apache.xpath.internal.jaxp;
27
28 import com.sun.org.apache.xpath.internal.objects.XObject;
29 import java.util.Objects;
30 import javax.xml.transform.TransformerException;
31 import javax.xml.xpath.XPathNodes;
32 import javax.xml.xpath.XPathEvaluationResult;
33 import javax.xml.xpath.XPathEvaluationResult.XPathResultType;
34 import org.w3c.dom.Node;
35 import org.w3c.dom.NodeList;
36 import org.w3c.dom.traversal.NodeIterator;
37
38 /**
39 * This is the implementation of XPathEvaluationResult that represents the
40 * result of the evaluation of an XPath expression within the context of a
41 * particular node.
42 */
43 class XPathResultImpl<T> implements XPathEvaluationResult<T> {
44
45 XObject resultObject;
46 int resultType;
47 Class<T> type;
48 XPathResultType mapToType;
49 NodeList nodeList = null;
50 int currentIndex;
51 Node currentNode;
52
53 boolean boolValue = false;
54 Node node = null;
55 double numValue;
56 String strValue;
57
58 /**
59 * Construct an XPathEvaluationResult object.
60 *
61 * @param resultObject internal XPath result object
62 * @param type class type
63 * @throws TransformerException if there is an error reading the XPath
64 * result.
65 */
66 public XPathResultImpl(XObject resultObject, Class<T> type)
67 throws TransformerException {
68 this.resultObject = resultObject;
69 resultType = resultObject.getType();
70 this.type = type;
71 getResult(resultObject);
72 }
73
74 /**
75 * Return the result type as an enum specified by {@code XPathResultType}
76 * @return the result type
77 */
78 @Override
79 public XPathResultType type() {
80 return mapToType;
81 }
82
83 /**
84 * Returns the value of the result as the type <T> specified for the class.
85 *
86 * @return The value of the result.
87 */
88 @Override
89 public T value() {
90 Objects.requireNonNull(type);
91 try {
92 return getValue(resultObject, type);
93 } catch (TransformerException ex) {
94 throw new RuntimeException(ex);
95 }
96 }
97
98
99 /**
100 * Read the XObject and set values in accordance with the result type
101 * @param resultObject internal XPath result object
102 * @throws TransformerException if there is an error reading the XPath
103 * result.
104 */
105 private void getResult(XObject resultObject) throws TransformerException {
106 switch (resultType) {
107 case XObject.CLASS_BOOLEAN:
108 boolValue = resultObject.bool();
109 mapToType = XPathResultType.BOOLEAN;
110 break;
111 case XObject.CLASS_NUMBER:
112 numValue = resultObject.num();
113 mapToType = XPathResultType.NUMBER;
114 break;
115 case XObject.CLASS_STRING:
116 strValue = resultObject.str();
117 mapToType = XPathResultType.STRING;
118 break;
119 case XObject.CLASS_NODESET:
120 mapToType = XPathResultType.NODESET;
121 nodeList = resultObject.nodelist();
122 break;
123 case XObject.CLASS_RTREEFRAG: //NODE
124 mapToType = XPathResultType.NODE;
125 NodeIterator ni = resultObject.nodeset();
126 //Return the first node, or null
127 node = ni.nextNode();
128 break;
129 }
130 }
131
132 /**
133 * Read the internal result object and return the value in accordance with
134 * the type specified.
135 *
136 * @param <T> The expected class type.
137 * @param resultObject internal XPath result object
138 * @param type the class type
139 * @return The value of the result.
140 * @throws TransformerException if there is an error reading the XPath
141 * result.
142 */
143 static <T> T getValue(XObject resultObject, Class<T> type) throws TransformerException {
144 Objects.requireNonNull(type);
145 if (type.isAssignableFrom(XPathEvaluationResult.class)) {
146 return type.cast(new XPathResultImpl<T>(resultObject, type));
147 }
148 int resultType = classToInternalType(type);
149 switch (resultType) {
150 case XObject.CLASS_BOOLEAN:
151 return type.cast(resultObject.bool());
152 case XObject.CLASS_NUMBER:
153 if (Double.class.isAssignableFrom(type)) {
154 return type.cast(resultObject.num());
155 } else if (Integer.class.isAssignableFrom(type)) {
156 return type.cast((int) resultObject.num());
157 } else if (Number.class.isAssignableFrom(type)) {
158 return type.cast(resultObject.num());
159 }
160 case XObject.CLASS_STRING:
161 return type.cast(resultObject.str());
162 case XObject.CLASS_NODESET:
163 XPathNodes nodeSet = new XPathNodesImpl(resultObject.nodelist(),
164 classToType(Node.class), Node.class);
165 return type.cast(nodeSet);
166 case XObject.CLASS_RTREEFRAG: //NODE
167 NodeIterator ni = resultObject.nodeset();
168 //Return the first node, or null
169 return type.cast(ni.nextNode());
170 }
171
172 return null;
173 }
174
175 /**
176 * Map class types to the XPathResultType
177 *
178 * @param <T> The expected class type.
179 * @param type the class type
180 * @return an XPathResultType enum type
181 */
182 static <T> XPathResultType classToType(Class<T> type) {
183 if (type.isAssignableFrom(Boolean.class)) {
184 return XPathResultType.BOOLEAN;
185 } else if (type.isAssignableFrom(Double.class)) {
186 return XPathResultType.NUMBER;
187 } else if (type.isAssignableFrom(String.class)) {
188 return XPathResultType.STRING;
189 } else if (type.isAssignableFrom(NodeList.class)) {
190 return XPathResultType.NODESET;
191 } else if (type.isAssignableFrom(Node.class)) {
192 return XPathResultType.NODE;
193 }
194 return XPathResultType.ANY;
195 }
196
197 /**
198 * Map the specified class type to the internal result type
199 *
200 * @param <T> The expected class type.
201 * @param type the class type
202 * @return the internal XObject type.
203 */
204 static <T> int classToInternalType(Class<T> type) {
205 if (type.isAssignableFrom(Boolean.class)) {
206 return XObject.CLASS_BOOLEAN;
207 } else if (Number.class.isAssignableFrom(type)) {
208 return XObject.CLASS_NUMBER;
209 } else if (type.isAssignableFrom(String.class)) {
210 return XObject.CLASS_STRING;
211 } else if (type.isAssignableFrom(XPathNodes.class)) {
212 return XObject.CLASS_NODESET;
213 } else if (type.isAssignableFrom(Node.class)) {
214 return XObject.CLASS_RTREEFRAG;
215 }
216 return XObject.CLASS_NULL;
217 }
218 }