001 /**
002 *
003 * Licensed to the Apache Software Foundation (ASF) under one or more
004 * contributor license agreements. See the NOTICE file distributed with
005 * this work for additional information regarding copyright ownership.
006 * The ASF licenses this file to You under the Apache License, Version 2.0
007 * (the "License"); you may not use this file except in compliance with
008 * the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018 package org.apache.camel.impl;
019
020 import org.apache.camel.Predicate;
021 import org.apache.camel.Exchange;
022 import org.apache.camel.Expression;
023 import org.apache.camel.util.ObjectHelper;
024 import static org.apache.camel.util.ObjectHelper.notNull;
025
026 /**
027 * A useful base class for {@link Predicate} implementations
028 *
029 * @version $Revision: 1.1 $
030 */
031 public abstract class BinaryPredicateSupport<E extends Exchange> implements Predicate<E> {
032
033 private final Expression<E> left;
034 private final Expression<E> right;
035
036 protected BinaryPredicateSupport(Expression<E> left, Expression<E> right) {
037 notNull(left, "left");
038 notNull(right, "right");
039
040 this.left = left;
041 this.right = right;
042 }
043
044 @Override
045 public String toString() {
046 return left + " " + getOperationText() + " " + right;
047 }
048
049 public boolean matches(E exchange) {
050 Object leftValue = left.evaluate(exchange);
051 Object rightValue = right.evaluate(exchange);
052 return matches(exchange, leftValue, rightValue);
053 }
054
055 public void assertMatches(String text, E exchange) {
056 Object leftValue = left.evaluate(exchange);
057 Object rightValue = right.evaluate(exchange);
058 if (!matches(exchange, leftValue, rightValue)) {
059 throw new AssertionError(assertionFailureMessage(exchange, leftValue, rightValue));
060 }
061 }
062
063 protected abstract boolean matches(E exchange, Object leftValue, Object rightValue);
064
065 protected abstract String getOperationText();
066
067 protected String assertionFailureMessage(E exchange, Object leftValue, Object rightValue) {
068 return this + " failed on " + exchange + " with left value <" + leftValue + "> right value <" + rightValue + ">";
069 }
070 }