- /*
- * Copyright 1999-2004 The Apache Software Foundation
- *
- * Licensed 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.HashSet;
-
- import org.apache.commons.jxpath.BasicNodeSet;
- 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: 1.12 $ $Date: 2004/02/29 14:17:38 $
- */
- public class UnionContext extends NodeSetContext {
- private boolean startedSet = false;
- private EvalContext contexts[];
- private boolean prepared = false;
-
- public UnionContext(EvalContext parentContext, EvalContext contexts[]) {
- super(parentContext, new BasicNodeSet());
- this.contexts = contexts;
- }
-
- public int getDocumentOrder() {
- if (contexts.length > 1) {
- return 1;
- }
- return super.getDocumentOrder();
- }
-
- public boolean setPosition(int position) {
- if (!prepared) {
- prepared = true;
- BasicNodeSet nodeSet = (BasicNodeSet) getNodeSet();
- HashSet set = new HashSet();
- for (int i = 0; i < contexts.length; i++) {
- EvalContext ctx = (EvalContext) contexts[i];
- while (ctx.nextSet()) {
- while (ctx.nextNode()) {
- NodePointer ptr = ctx.getCurrentNodePointer();
- if (!set.contains(ptr)) {
- nodeSet.add(ptr);
- set.add(ptr);
- }
- }
- }
- }
- }
- return super.setPosition(position);
- }
- }