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.processor; 018 019import java.util.Iterator; 020 021import org.apache.camel.CamelContext; 022import org.apache.camel.Exchange; 023import org.apache.camel.Expression; 024import org.apache.camel.util.ObjectHelper; 025 026/** 027 * Implements a <a href="http://camel.apache.org/dynamic-router.html">Dynamic Router</a> pattern 028 * where the destination(s) is computed at runtime. 029 * <p/> 030 * This implementation builds on top of {@link org.apache.camel.processor.RoutingSlip} which contains 031 * the most logic. 032 * 033 * @version 034 */ 035public class DynamicRouter extends RoutingSlip { 036 037 public DynamicRouter(CamelContext camelContext) { 038 super(camelContext); 039 } 040 041 public DynamicRouter(CamelContext camelContext, Expression expression, String uriDelimiter) { 042 super(camelContext, expression, uriDelimiter); 043 } 044 045 @Override 046 protected RoutingSlipIterator createRoutingSlipIterator(Exchange exchange) throws Exception { 047 return new DynamicRoutingSlipIterator(expression); 048 } 049 050 /** 051 * The dynamic routing slip iterator. 052 */ 053 private final class DynamicRoutingSlipIterator implements RoutingSlipIterator { 054 055 private final Expression slip; 056 private Iterator<?> current; 057 058 private DynamicRoutingSlipIterator(Expression slip) { 059 this.slip = slip; 060 } 061 062 public boolean hasNext(Exchange exchange) { 063 if (current != null && current.hasNext()) { 064 return true; 065 } 066 // evaluate next slip 067 Object routingSlip = slip.evaluate(exchange, Object.class); 068 if (routingSlip == null) { 069 return false; 070 } 071 current = ObjectHelper.createIterator(routingSlip, uriDelimiter); 072 return current != null && current.hasNext(); 073 } 074 075 public Object next(Exchange exchange) { 076 return current.next(); 077 } 078 } 079}