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 package org.apache.camel.model;
018
019 import java.util.ArrayList;
020 import java.util.List;
021 import javax.xml.bind.annotation.XmlAccessType;
022 import javax.xml.bind.annotation.XmlAccessorType;
023 import javax.xml.bind.annotation.XmlRootElement;
024 import javax.xml.bind.annotation.XmlTransient;
025
026 import org.apache.camel.Predicate;
027 import org.apache.camel.Processor;
028 import org.apache.camel.processor.Pipeline;
029 import org.apache.camel.spi.InterceptStrategy;
030 import org.apache.camel.spi.RouteContext;
031
032 /**
033 * Represents an XML <intercept/> element
034 *
035 * @version $Revision: 788663 $
036 */
037 @XmlRootElement(name = "intercept")
038 @XmlAccessorType(XmlAccessType.FIELD)
039 public class InterceptDefinition extends OutputDefinition<ProcessorDefinition> {
040
041 // TODO: support stop later (its a bit hard as it needs to break entire processing of route)
042
043 @XmlTransient
044 protected Processor output;
045
046 @XmlTransient
047 protected final List<Processor> intercepted = new ArrayList<Processor>();
048
049 public InterceptDefinition() {
050 }
051
052 @Override
053 public String toString() {
054 return "Intercept[" + getOutputs() + "]";
055 }
056
057 @Override
058 public String getShortName() {
059 return "intercept";
060 }
061
062 @Override
063 public String getLabel() {
064 return "intercept";
065 }
066
067 @Override
068 public Processor createProcessor(final RouteContext routeContext) throws Exception {
069 // create the output processor
070 output = createOutputsProcessor(routeContext);
071
072 // add the output as a intercept strategy to the route context so its invoked on each processing step
073 routeContext.getInterceptStrategies().add(new InterceptStrategy() {
074 private Processor interceptedTarget;
075
076 public Processor wrapProcessorInInterceptors(ProcessorDefinition processorDefinition, Processor target, Processor nextTarget) throws Exception {
077 // prefer next target over taget as next target is the real target
078 interceptedTarget = nextTarget != null ? nextTarget : target;
079
080 // remember the target that was intercepted
081 intercepted.add(interceptedTarget);
082
083 if (interceptedTarget != null) {
084 // wrap in a pipeline so we continue routing to the next
085 List<Processor> list = new ArrayList<Processor>(2);
086 list.add(output);
087 list.add(interceptedTarget);
088 return new Pipeline(list);
089 } else {
090 return output;
091 }
092 }
093
094 @Override
095 public String toString() {
096 return "intercept[" + (interceptedTarget != null ? interceptedTarget : output) + "]";
097 }
098 });
099
100 // remove me from the route so I am not invoked in a regular route path
101 routeContext.getRoute().getOutputs().remove(this);
102 // and return no processor to invoke next from me
103 return null;
104 }
105
106 /**
107 * Applies this interceptor only if the given predicate is true
108 *
109 * @param predicate the predicate
110 * @return the builder
111 */
112 public ChoiceDefinition when(Predicate predicate) {
113 return choice().when(predicate);
114 }
115
116 /**
117 * This method is <b>only</b> for handling some post configuration
118 * that is needed from the Spring DSL side as JAXB does not invoke the fluent
119 * builders, so we need to manually handle this afterwards, and since this is
120 * an interceptor it has to do a bit of magic logic to fixup to handle predicates
121 * with or without proceed/stop set as well.
122 */
123 public void afterPropertiesSet() {
124 if (getOutputs().size() == 0) {
125 // no outputs
126 return;
127 }
128
129 ProcessorDefinition first = getOutputs().get(0);
130 if (first instanceof WhenDefinition) {
131 WhenDefinition when = (WhenDefinition) first;
132 // move this outputs to the when, expect the first one
133 // as the first one is the interceptor itself
134 for (int i = 1; i < outputs.size(); i++) {
135 ProcessorDefinition out = outputs.get(i);
136 when.addOutput(out);
137 }
138 // remove the moved from the original output, by just keeping the first one
139 ProcessorDefinition keep = outputs.get(0);
140 clearOutput();
141 outputs.add(keep);
142 }
143 }
144
145 public Processor getInterceptedProcessor(int index) {
146 // avoid out of bounds
147 if (index <= intercepted.size() - 1) {
148 return intercepted.get(index);
149 } else {
150 return null;
151 }
152 }
153
154 }