1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.jxpath.ri.compiler;
18
19 import org.apache.commons.jxpath.ri.EvalContext;
20 import org.apache.commons.jxpath.ri.axes.UnionContext;
21
22 /**
23 * Implementation of {@link Expression} for the operation "|".
24 *
25 * @author Dmitri Plotnikov
26 * @version $Revision: 652845 $ $Date: 2008-05-02 19:46:46 +0200 (Fr, 02 Mai 2008) $
27 */
28 public class CoreOperationUnion extends CoreOperation {
29
30 /**
31 * Create a new CoreOperationUnion.
32 * @param args Expression[]
33 */
34 public CoreOperationUnion(Expression[] args) {
35 super(args);
36 }
37
38 public Object computeValue(EvalContext context) {
39 EvalContext[] argCtxs = new EvalContext[args.length];
40 for (int i = 0; i < args.length; i++) {
41 Object value = args[i].compute(context);
42 if (value instanceof EvalContext) {
43 argCtxs[i] = (EvalContext) value;
44 }
45 else {
46 argCtxs[i] = context.getRootContext().getConstantContext(value);
47 }
48 }
49 return new UnionContext(context.getRootContext(), argCtxs);
50 }
51
52 protected int getPrecedence() {
53 return UNION_PRECEDENCE;
54 }
55
56 protected boolean isSymmetric() {
57 return true;
58 }
59
60 public String getSymbol() {
61 return "|";
62 }
63 }