/*
* 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.
/**
* 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!
/**
* 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
/**
* Constructor for UnionChildIterator
*/
public UnionChildIterator()
{
super(null);
}
Add a node test to the union list.
Params: - 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.
/**
* 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.
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);
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.
Params: - n – The node to check to see if it passes the filter or not.
Returns: a constant to determine whether the node is accepted,
rejected, or skipped, as defined above .
/**
* 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;
}
}