/*
* 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.
*/
package org.apache.commons.jxpath.ri.axes;
import java.util.ArrayList;
import java.util.Iterator;
import org.apache.commons.jxpath.BasicNodeSet;
import org.apache.commons.jxpath.Pointer;
import org.apache.commons.jxpath.ri.EvalContext;
import org.apache.commons.jxpath.ri.model.NodePointer;
/**
* EvalContext that represents a union between other contexts - result
* of a union operation like (a | b)
*
* @author Dmitri Plotnikov
* @version $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $
*/
public class UnionContext extends NodeSetContext {
private EvalContext[] contexts;
private boolean prepared;
/**
* Create a new UnionContext.
* @param parentContext parent context
* @param contexts child contexts
*/
public UnionContext(EvalContext parentContext, EvalContext[] contexts) {
super(parentContext, new BasicNodeSet());
this.contexts = contexts;
}
public int getDocumentOrder() {
return contexts.length > 1 ? 1 : super.getDocumentOrder();
}
public boolean setPosition(int position) {
if (!prepared) {
prepared = true;
BasicNodeSet nodeSet = (BasicNodeSet) getNodeSet();
ArrayList pointers = new ArrayList();
for (int i = 0; i < contexts.length; i++) {
EvalContext ctx = (EvalContext) contexts[i];
while (ctx.nextSet()) {
while (ctx.nextNode()) {
NodePointer ptr = ctx.getCurrentNodePointer();
if (!pointers.contains(ptr)) {
pointers.add(ptr);
}
}
}
}
sortPointers(pointers);
for (Iterator it = pointers.iterator(); it.hasNext();) {
nodeSet.add((Pointer) it.next());
}
}
return super.setPosition(position);
}
}