| /* |
| * 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. |
| */ |
| /* |
| * $Id: UnionChildIterator.java 468655 2006-10-28 07:12:06Z minchau $ |
| */ |
| package org.apache.xpath.axes; |
| |
| import org.apache.xml.dtm.DTMIterator; |
| import org.apache.xpath.XPathContext; |
| import org.apache.xpath.objects.XObject; |
| import org.apache.xpath.patterns.NodeTest; |
| |
| /** |
| * This class defines a simplified type of union iterator that only |
| * tests along the child axes. If the conditions are right, it is |
| * much faster than using a UnionPathIterator. |
| */ |
| public class UnionChildIterator extends ChildTestIterator |
| { |
| static final long serialVersionUID = 3500298482193003495L; |
| /** |
| * Even though these may hold full LocPathIterators, this array does |
| * not have to be cloned, since only the node test and predicate |
| * portion are used, and these only need static information. However, |
| * also note that index predicates can not be used! |
| */ |
| private PredicatedNodeTest[] m_nodeTests = null; |
| |
| /** |
| * Constructor for UnionChildIterator |
| */ |
| public UnionChildIterator() |
| { |
| super(null); |
| } |
| |
| /** |
| * Add a node test to the union list. |
| * |
| * @param test reference to a NodeTest, which will be added |
| * directly to the list of node tests (in other words, it will |
| * not be cloned). The parent of this test will be set to |
| * this object. |
| */ |
| public void addNodeTest(PredicatedNodeTest test) |
| { |
| |
| // Increase array size by only 1 at a time. Fix this |
| // if it looks to be a problem. |
| if (null == m_nodeTests) |
| { |
| m_nodeTests = new PredicatedNodeTest[1]; |
| m_nodeTests[0] = test; |
| } |
| else |
| { |
| PredicatedNodeTest[] tests = m_nodeTests; |
| int len = m_nodeTests.length; |
| |
| m_nodeTests = new PredicatedNodeTest[len + 1]; |
| |
| System.arraycopy(tests, 0, m_nodeTests, 0, len); |
| |
| m_nodeTests[len] = test; |
| } |
| test.exprSetParent(this); |
| } |
| |
| /** |
| * 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); |
| if (m_nodeTests != null) { |
| for (int i = 0; i < m_nodeTests.length; i++) { |
| m_nodeTests[i].fixupVariables(vars, globalsSize); |
| } |
| } |
| } |
| |
| /** |
| * Test whether a specified node is visible in the logical view of a |
| * TreeWalker or NodeIterator. This function will be called by the |
| * implementation of TreeWalker and NodeIterator; it is not intended to |
| * be called directly from user code. |
| * @param n The node to check to see if it passes the filter or not. |
| * @return a constant to determine whether the node is accepted, |
| * rejected, or skipped, as defined above . |
| */ |
| public short acceptNode(int n) |
| { |
| XPathContext xctxt = getXPathContext(); |
| try |
| { |
| xctxt.pushCurrentNode(n); |
| for (int i = 0; i < m_nodeTests.length; i++) |
| { |
| PredicatedNodeTest pnt = m_nodeTests[i]; |
| XObject score = pnt.execute(xctxt, n); |
| if (score != NodeTest.SCORE_NONE) |
| { |
| // Note that we are assuming there are no positional predicates! |
| if (pnt.getPredicateCount() > 0) |
| { |
| if (pnt.executePredicates(n, xctxt)) |
| return DTMIterator.FILTER_ACCEPT; |
| } |
| else |
| return DTMIterator.FILTER_ACCEPT; |
| |
| } |
| } |
| } |
| catch (javax.xml.transform.TransformerException se) |
| { |
| |
| // TODO: Fix this. |
| throw new RuntimeException(se.getMessage()); |
| } |
| finally |
| { |
| xctxt.popCurrentNode(); |
| } |
| return DTMIterator.FILTER_SKIP; |
| } |
| |
| } |