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.camel.support;
018
019import org.apache.camel.Exchange;
020import org.apache.camel.Expression;
021import org.apache.camel.Predicate;
022import org.apache.camel.util.ObjectHelper;
023
024/**
025 * A useful base class for {@link Predicate} and {@link Expression} implementations
026 *
027 * @version 
028 */
029public abstract class ExpressionSupport implements Expression, Predicate {
030
031    public boolean matches(Exchange exchange) {
032        Object value = evaluate(exchange, Object.class);
033        return ObjectHelper.evaluateValuePredicate(value);
034    }
035
036    public Object evaluate(Exchange exchange) {
037        return evaluate(exchange, Object.class);
038    }
039
040    public void assertMatches(String text, Exchange exchange) {
041        if (!matches(exchange)) {
042            throw new AssertionError(text + " " + assertionFailureMessage(exchange) + " for exchange: " + exchange);
043        }
044    }
045
046    protected abstract String assertionFailureMessage(Exchange exchange);
047}