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 /* 19 * $Id: VarNameCollector.java 468643 2006-10-28 06:56:03Z minchau $ 20 */ 21 package org.apache.xalan.templates; 22 23 import java.util.Vector; 24 25 import org.apache.xml.utils.QName; 26 import org.apache.xpath.ExpressionOwner; 27 import org.apache.xpath.XPathVisitor; 28 import org.apache.xpath.operations.Variable; 29 30 /** 31 * This class visits variable refs in an XPath and collects their QNames. 32 */ 33 public class VarNameCollector extends XPathVisitor 34 { 35 Vector m_refs = new Vector(); 36 37 /** 38 * Reset the list for a fresh visitation and collection. 39 */ 40 public void reset() 41 { 42 m_refs.removeAllElements(); //.clear(); 43 } 44 45 /** 46 * Get the number of variable references that were collected. 47 * @return the size of the list. 48 */ 49 public int getVarCount() 50 { 51 return m_refs.size(); 52 } 53 54 /** 55 * Tell if the given qualified name occurs in 56 * the list of qualified names collected. 57 * 58 * @param refName Must be a valid qualified name. 59 * @return true if the list contains the qualified name. 60 */ 61 boolean doesOccur(QName refName) 62 { 63 return m_refs.contains(refName); 64 } 65 66 /** 67 * Visit a variable reference. 68 * @param owner The owner of the expression, to which the expression can 69 * be reset if rewriting takes place. 70 * @param var The variable reference object. 71 * @return true if the sub expressions should be traversed. 72 */ 73 public boolean visitVariableRef(ExpressionOwner owner, Variable var) 74 { 75 m_refs.addElement(var.getQName()); 76 return true; 77 } 78 79 } 80 81
