/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the  "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
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/*
 * $Id: FunctionPattern.java 468655 2006-10-28 07:12:06Z minchau $
 */
package org.apache.xpath.patterns;

import org.apache.xml.dtm.DTM;
import org.apache.xml.dtm.DTMIterator;
import org.apache.xpath.Expression;
import org.apache.xpath.ExpressionOwner;
import org.apache.xpath.XPathContext;
import org.apache.xpath.XPathVisitor;
import org.apache.xpath.objects.XNumber;
import org.apache.xpath.objects.XObject;

Match pattern step that contains a function.
@xsl.usageadvanced
/** * Match pattern step that contains a function. * @xsl.usage advanced */
public class FunctionPattern extends StepPattern { static final long serialVersionUID = -5426793413091209944L;
Construct a FunctionPattern from a expression. NEEDSDOC @param expr
/** * Construct a FunctionPattern from a * {@link org.apache.xpath.functions.Function expression}. * * NEEDSDOC @param expr */
public FunctionPattern(Expression expr, int axis, int predaxis) { super(0, null, null, axis, predaxis); m_functionExpr = expr; }
Static calc of match score.
/** * Static calc of match score. */
public final void calcScore() { m_score = SCORE_OTHER; if (null == m_targetString) calcTargetString(); }
Should be a expression. @serial
/** * Should be a {@link org.apache.xpath.functions.Function expression}. * @serial */
Expression m_functionExpr;
This function is used to fixup variables from QNames to stack frame indexes at stylesheet build time.
Params:
  • vars – List of QNames that correspond to variables. This list should be searched backwards for the first qualified name that corresponds to the variable reference qname. The position of the QName in the vector from the start of the vector will be its position in the stack frame (but variables above the globalsTop value will need to be offset to the current stack frame).
/** * This function is used to fixup variables from QNames to stack frame * indexes at stylesheet build time. * @param vars List of QNames that correspond to variables. This list * should be searched backwards for the first qualified name that * corresponds to the variable reference qname. The position of the * QName in the vector from the start of the vector will be its position * in the stack frame (but variables above the globalsTop value will need * to be offset to the current stack frame). */
public void fixupVariables(java.util.Vector vars, int globalsSize) { super.fixupVariables(vars, globalsSize); m_functionExpr.fixupVariables(vars, globalsSize); }
Test a node to see if it matches the given node test.
Params:
  • xctxt – XPath runtime context.
Throws:
Returns:NodeTest.SCORE_NODETEST, NodeTest.SCORE_NONE, NodeTest.SCORE_NSWILD, NodeTest.SCORE_QNAME, or NodeTest.SCORE_OTHER.
/** * Test a node to see if it matches the given node test. * * @param xctxt XPath runtime context. * * @return {@link org.apache.xpath.patterns.NodeTest#SCORE_NODETEST}, * {@link org.apache.xpath.patterns.NodeTest#SCORE_NONE}, * {@link org.apache.xpath.patterns.NodeTest#SCORE_NSWILD}, * {@link org.apache.xpath.patterns.NodeTest#SCORE_QNAME}, or * {@link org.apache.xpath.patterns.NodeTest#SCORE_OTHER}. * * @throws javax.xml.transform.TransformerException */
public XObject execute(XPathContext xctxt, int context) throws javax.xml.transform.TransformerException { DTMIterator nl = m_functionExpr.asIterator(xctxt, context); XNumber score = SCORE_NONE; if (null != nl) { int n; while (DTM.NULL != (n = nl.nextNode())) { score = (n == context) ? SCORE_OTHER : SCORE_NONE; if (score == SCORE_OTHER) { context = n; break; } } // nl.detach(); } nl.detach(); return score; }
Test a node to see if it matches the given node test.
Params:
  • xctxt – XPath runtime context.
Throws:
Returns:NodeTest.SCORE_NODETEST, NodeTest.SCORE_NONE, NodeTest.SCORE_NSWILD, NodeTest.SCORE_QNAME, or NodeTest.SCORE_OTHER.
/** * Test a node to see if it matches the given node test. * * @param xctxt XPath runtime context. * * @return {@link org.apache.xpath.patterns.NodeTest#SCORE_NODETEST}, * {@link org.apache.xpath.patterns.NodeTest#SCORE_NONE}, * {@link org.apache.xpath.patterns.NodeTest#SCORE_NSWILD}, * {@link org.apache.xpath.patterns.NodeTest#SCORE_QNAME}, or * {@link org.apache.xpath.patterns.NodeTest#SCORE_OTHER}. * * @throws javax.xml.transform.TransformerException */
public XObject execute(XPathContext xctxt, int context, DTM dtm, int expType) throws javax.xml.transform.TransformerException { DTMIterator nl = m_functionExpr.asIterator(xctxt, context); XNumber score = SCORE_NONE; if (null != nl) { int n; while (DTM.NULL != (n = nl.nextNode())) { score = (n == context) ? SCORE_OTHER : SCORE_NONE; if (score == SCORE_OTHER) { context = n; break; } } nl.detach(); } return score; }
Test a node to see if it matches the given node test.
Params:
  • xctxt – XPath runtime context.
Throws:
Returns:NodeTest.SCORE_NODETEST, NodeTest.SCORE_NONE, NodeTest.SCORE_NSWILD, NodeTest.SCORE_QNAME, or NodeTest.SCORE_OTHER.
/** * Test a node to see if it matches the given node test. * * @param xctxt XPath runtime context. * * @return {@link org.apache.xpath.patterns.NodeTest#SCORE_NODETEST}, * {@link org.apache.xpath.patterns.NodeTest#SCORE_NONE}, * {@link org.apache.xpath.patterns.NodeTest#SCORE_NSWILD}, * {@link org.apache.xpath.patterns.NodeTest#SCORE_QNAME}, or * {@link org.apache.xpath.patterns.NodeTest#SCORE_OTHER}. * * @throws javax.xml.transform.TransformerException */
public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException { int context = xctxt.getCurrentNode(); DTMIterator nl = m_functionExpr.asIterator(xctxt, context); XNumber score = SCORE_NONE; if (null != nl) { int n; while (DTM.NULL != (n = nl.nextNode())) { score = (n == context) ? SCORE_OTHER : SCORE_NONE; if (score == SCORE_OTHER) { context = n; break; } } nl.detach(); } return score; } class FunctionOwner implements ExpressionOwner {
See Also:
  • getExpression.getExpression()
/** * @see ExpressionOwner#getExpression() */
public Expression getExpression() { return m_functionExpr; }
See Also:
  • setExpression.setExpression(Expression)
/** * @see ExpressionOwner#setExpression(Expression) */
public void setExpression(Expression exp) { exp.exprSetParent(FunctionPattern.this); m_functionExpr = exp; } }
Call the visitor for the function.
/** * Call the visitor for the function. */
protected void callSubtreeVisitors(XPathVisitor visitor) { m_functionExpr.callVisitors(new FunctionOwner(), visitor); super.callSubtreeVisitors(visitor); } }