001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the "License");
007 * you may not use this file except in compliance with the License.
008 * You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018 /*
019 * $Id: FunctionPattern.java 468655 2006-10-28 07:12:06Z minchau $
020 */
021 package org.apache.xpath.patterns;
022
023 import org.apache.xml.dtm.DTM;
024 import org.apache.xml.dtm.DTMIterator;
025 import org.apache.xpath.Expression;
026 import org.apache.xpath.ExpressionOwner;
027 import org.apache.xpath.XPathContext;
028 import org.apache.xpath.XPathVisitor;
029 import org.apache.xpath.objects.XNumber;
030 import org.apache.xpath.objects.XObject;
031
032 /**
033 * Match pattern step that contains a function.
034 * @xsl.usage advanced
035 */
036 public class FunctionPattern extends StepPattern
037 {
038 static final long serialVersionUID = -5426793413091209944L;
039
040 /**
041 * Construct a FunctionPattern from a
042 * {@link org.apache.xpath.functions.Function expression}.
043 *
044 * NEEDSDOC @param expr
045 */
046 public FunctionPattern(Expression expr, int axis, int predaxis)
047 {
048
049 super(0, null, null, axis, predaxis);
050
051 m_functionExpr = expr;
052 }
053
054 /**
055 * Static calc of match score.
056 */
057 public final void calcScore()
058 {
059
060 m_score = SCORE_OTHER;
061
062 if (null == m_targetString)
063 calcTargetString();
064 }
065
066 /**
067 * Should be a {@link org.apache.xpath.functions.Function expression}.
068 * @serial
069 */
070 Expression m_functionExpr;
071
072 /**
073 * This function is used to fixup variables from QNames to stack frame
074 * indexes at stylesheet build time.
075 * @param vars List of QNames that correspond to variables. This list
076 * should be searched backwards for the first qualified name that
077 * corresponds to the variable reference qname. The position of the
078 * QName in the vector from the start of the vector will be its position
079 * in the stack frame (but variables above the globalsTop value will need
080 * to be offset to the current stack frame).
081 */
082 public void fixupVariables(java.util.Vector vars, int globalsSize)
083 {
084 super.fixupVariables(vars, globalsSize);
085 m_functionExpr.fixupVariables(vars, globalsSize);
086 }
087
088
089 /**
090 * Test a node to see if it matches the given node test.
091 *
092 * @param xctxt XPath runtime context.
093 *
094 * @return {@link org.apache.xpath.patterns.NodeTest#SCORE_NODETEST},
095 * {@link org.apache.xpath.patterns.NodeTest#SCORE_NONE},
096 * {@link org.apache.xpath.patterns.NodeTest#SCORE_NSWILD},
097 * {@link org.apache.xpath.patterns.NodeTest#SCORE_QNAME}, or
098 * {@link org.apache.xpath.patterns.NodeTest#SCORE_OTHER}.
099 *
100 * @throws javax.xml.transform.TransformerException
101 */
102 public XObject execute(XPathContext xctxt, int context)
103 throws javax.xml.transform.TransformerException
104 {
105
106 DTMIterator nl = m_functionExpr.asIterator(xctxt, context);
107 XNumber score = SCORE_NONE;
108
109 if (null != nl)
110 {
111 int n;
112
113 while (DTM.NULL != (n = nl.nextNode()))
114 {
115 score = (n == context) ? SCORE_OTHER : SCORE_NONE;
116
117 if (score == SCORE_OTHER)
118 {
119 context = n;
120
121 break;
122 }
123 }
124
125 // nl.detach();
126 }
127 nl.detach();
128
129 return score;
130 }
131
132 /**
133 * Test a node to see if it matches the given node test.
134 *
135 * @param xctxt XPath runtime context.
136 *
137 * @return {@link org.apache.xpath.patterns.NodeTest#SCORE_NODETEST},
138 * {@link org.apache.xpath.patterns.NodeTest#SCORE_NONE},
139 * {@link org.apache.xpath.patterns.NodeTest#SCORE_NSWILD},
140 * {@link org.apache.xpath.patterns.NodeTest#SCORE_QNAME}, or
141 * {@link org.apache.xpath.patterns.NodeTest#SCORE_OTHER}.
142 *
143 * @throws javax.xml.transform.TransformerException
144 */
145 public XObject execute(XPathContext xctxt, int context,
146 DTM dtm, int expType)
147 throws javax.xml.transform.TransformerException
148 {
149
150 DTMIterator nl = m_functionExpr.asIterator(xctxt, context);
151 XNumber score = SCORE_NONE;
152
153 if (null != nl)
154 {
155 int n;
156
157 while (DTM.NULL != (n = nl.nextNode()))
158 {
159 score = (n == context) ? SCORE_OTHER : SCORE_NONE;
160
161 if (score == SCORE_OTHER)
162 {
163 context = n;
164
165 break;
166 }
167 }
168
169 nl.detach();
170 }
171
172 return score;
173 }
174
175 /**
176 * Test a node to see if it matches the given node test.
177 *
178 * @param xctxt XPath runtime context.
179 *
180 * @return {@link org.apache.xpath.patterns.NodeTest#SCORE_NODETEST},
181 * {@link org.apache.xpath.patterns.NodeTest#SCORE_NONE},
182 * {@link org.apache.xpath.patterns.NodeTest#SCORE_NSWILD},
183 * {@link org.apache.xpath.patterns.NodeTest#SCORE_QNAME}, or
184 * {@link org.apache.xpath.patterns.NodeTest#SCORE_OTHER}.
185 *
186 * @throws javax.xml.transform.TransformerException
187 */
188 public XObject execute(XPathContext xctxt)
189 throws javax.xml.transform.TransformerException
190 {
191
192 int context = xctxt.getCurrentNode();
193 DTMIterator nl = m_functionExpr.asIterator(xctxt, context);
194 XNumber score = SCORE_NONE;
195
196 if (null != nl)
197 {
198 int n;
199
200 while (DTM.NULL != (n = nl.nextNode()))
201 {
202 score = (n == context) ? SCORE_OTHER : SCORE_NONE;
203
204 if (score == SCORE_OTHER)
205 {
206 context = n;
207
208 break;
209 }
210 }
211
212 nl.detach();
213 }
214
215 return score;
216 }
217
218 class FunctionOwner implements ExpressionOwner
219 {
220 /**
221 * @see ExpressionOwner#getExpression()
222 */
223 public Expression getExpression()
224 {
225 return m_functionExpr;
226 }
227
228
229 /**
230 * @see ExpressionOwner#setExpression(Expression)
231 */
232 public void setExpression(Expression exp)
233 {
234 exp.exprSetParent(FunctionPattern.this);
235 m_functionExpr = exp;
236 }
237 }
238
239 /**
240 * Call the visitor for the function.
241 */
242 protected void callSubtreeVisitors(XPathVisitor visitor)
243 {
244 m_functionExpr.callVisitors(new FunctionOwner(), visitor);
245 super.callSubtreeVisitors(visitor);
246 }
247
248 }