001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *     http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.jxpath.ri.compiler;
019
020import org.apache.commons.jxpath.ri.EvalContext;
021import org.apache.commons.jxpath.ri.axes.UnionContext;
022
023/**
024 * Implementation of {@link Expression} for the operation "|".
025 */
026public class CoreOperationUnion extends CoreOperation {
027
028    /**
029     * Constructs a new CoreOperationUnion.
030     *
031     * @param args Expression[]
032     */
033    public CoreOperationUnion(final Expression[] args) {
034        super(args);
035    }
036
037    @Override
038    public Object computeValue(final EvalContext context) {
039        final EvalContext[] argCtxs = new EvalContext[args.length];
040        for (int i = 0; i < args.length; i++) {
041            final Object value = args[i].compute(context);
042            if (value instanceof EvalContext) {
043                argCtxs[i] = (EvalContext) value;
044            } else {
045                argCtxs[i] = context.getRootContext().getConstantContext(value);
046            }
047        }
048        return new UnionContext(context.getRootContext(), argCtxs);
049    }
050
051    @Override
052    protected int getPrecedence() {
053        return UNION_PRECEDENCE;
054    }
055
056    @Override
057    public String getSymbol() {
058        return "|";
059    }
060
061    @Override
062    protected boolean isSymmetric() {
063        return true;
064    }
065}