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 */
017package org.apache.activemq.filter;
018
019import javax.jms.JMSException;
020
021/**
022 * Used to evaluate an XQuery Expression in a JMS selector.
023 */
024public final class XQueryExpression implements BooleanExpression {
025    private final String xpath;
026
027    XQueryExpression(String xpath) {
028        super();
029        this.xpath = xpath;
030    }
031
032    public Object evaluate(MessageEvaluationContext message) throws JMSException {
033        return Boolean.FALSE;
034    }
035
036    public String toString() {
037        return "XQUERY " + ConstantExpression.encodeString(xpath);
038    }
039
040    /**
041     * @param message
042     * @return true if the expression evaluates to Boolean.TRUE.
043     * @throws JMSException
044     */
045    public boolean matches(MessageEvaluationContext message) throws JMSException {
046        Object object = evaluate(message);
047        return object != null && object == Boolean.TRUE;
048    }
049
050}