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 /** 40 * This is the implementation of XPathEvaluationResult that represents the 41 * result of the evaluation of an XPath expression within the context of a 42 * particular node. 43 */ 44 class XPathResultImpl<T> implements XPathEvaluationResult<T> { 45 46 XObject resultObject; 47 int resultType; 48 Class<T> type; 49 XPathResultType mapToType; 50 NodeList nodeList = null; 51 int currentIndex; 52 Node currentNode; 53 54 boolean boolValue = false; 55 Node node = null; 56 double numValue; 57 String strValue; 58 59 /** 60 * Construct an XPathEvaluationResult object. 61 * 62 * @param resultObject internal XPath result object 63 * @param type class type 64 * @throws TransformerException if there is an error reading the XPath 65 * result. 66 */ XPathResultImpl(XObject resultObject, Class<T> type)67 public XPathResultImpl(XObject resultObject, Class<T> type) 68 throws TransformerException { 69 this.resultObject = resultObject; 70 resultType = resultObject.getType(); 71 this.type = type; 72 getResult(resultObject); 73 } 74 75 /** 76 * Return the result type as an enum specified by {@code XPathResultType} 77 * @return the result type 78 */ 79 @Override type()80 public XPathResultType type() { 81 return mapToType; 82 } 83 84 /** 85 * Returns the value of the result as the type <T> specified for the class. 86 * 87 * @return The value of the result. 88 */ 89 @Override value()90 public T value() { 91 Objects.requireNonNull(type); 92 try { 93 return getValue(resultObject, type); 94 } catch (TransformerException ex) { 95 throw new RuntimeException(ex); 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 */ getResult(XObject resultObject)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, null in case of unexpected type. 140 * @throws TransformerException if there is an error reading the XPath 141 * result. 142 */ getValue(XObject resultObject, Class<T> type)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 (Long.class.isAssignableFrom(type)) { 158 return type.cast((long)resultObject.num()); 159 } 160 /* 161 This is to suppress warnings. By the current specification, 162 among numeric types, only Double, Integer and Long are supported. 163 */ 164 break; 165 case XObject.CLASS_STRING: 166 return type.cast(resultObject.str()); 167 case XObject.CLASS_NODESET: 168 XPathNodes nodeSet = new XPathNodesImpl(resultObject.nodelist(), 169 Node.class); 170 return type.cast(nodeSet); 171 case XObject.CLASS_RTREEFRAG: //NODE 172 NodeIterator ni = resultObject.nodeset(); 173 //Return the first node, or null 174 return type.cast(ni.nextNode()); 175 } 176 177 return null; 178 } 179 180 /** 181 * Map the specified class type to the internal result type 182 * 183 * @param <T> The expected class type. 184 * @param type the class type 185 * @return the internal XObject type. 186 */ classToInternalType(Class<T> type)187 static <T> int classToInternalType(Class<T> type) { 188 if (type.isAssignableFrom(Boolean.class)) { 189 return XObject.CLASS_BOOLEAN; 190 } else if (Number.class.isAssignableFrom(type)) { 191 return XObject.CLASS_NUMBER; 192 } else if (type.isAssignableFrom(String.class)) { 193 return XObject.CLASS_STRING; 194 } else if (type.isAssignableFrom(XPathNodes.class)) { 195 return XObject.CLASS_NODESET; 196 } else if (type.isAssignableFrom(Node.class)) { 197 return XObject.CLASS_RTREEFRAG; 198 } 199 return XObject.CLASS_NULL; 200 } 201 } 202