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.Collection;
020    import java.util.List;
021    
022    import javax.xml.bind.annotation.XmlAccessType;
023    import javax.xml.bind.annotation.XmlAccessorType;
024    import javax.xml.bind.annotation.XmlAttribute;
025    import javax.xml.bind.annotation.XmlElement;
026    import javax.xml.bind.annotation.XmlElements;
027    import javax.xml.bind.annotation.XmlRootElement;
028    
029    import org.apache.camel.Exchange;
030    import org.apache.camel.Expression;
031    import org.apache.camel.Processor;
032    import org.apache.camel.model.loadbalancer.LoadBalancerType;
033    import org.apache.camel.model.loadbalancer.RandomLoadBalanceStrategy;
034    import org.apache.camel.model.loadbalancer.RoundRobinLoadBalanceStrategy;
035    import org.apache.camel.model.loadbalancer.StickyLoadBalanceStrategy;
036    import org.apache.camel.model.loadbalancer.TopicLoadBalanceStrategy;
037    import org.apache.camel.processor.SendProcessor;
038    import org.apache.camel.processor.loadbalancer.LoadBalancer;
039    import org.apache.camel.processor.loadbalancer.RandomLoadBalancer;
040    import org.apache.camel.processor.loadbalancer.RoundRobinLoadBalancer;
041    import org.apache.camel.processor.loadbalancer.StickyLoadBalancer;
042    import org.apache.camel.processor.loadbalancer.TopicLoadBalancer;
043    import org.apache.camel.spi.RouteContext;
044    import org.apache.camel.util.CollectionStringBuffer;
045    
046    /**
047     * Represents an XML <loadBalance/> element
048     */
049    @XmlRootElement(name = "loadBalance")
050    @XmlAccessorType(XmlAccessType.FIELD)
051    public class LoadBalanceType extends OutputType<LoadBalanceType> {
052        @XmlAttribute(required = false)
053        private String ref;
054    
055        @XmlElements({
056            @XmlElement(required = false, name = "roundRobin", type = RoundRobinLoadBalanceStrategy.class),
057            @XmlElement(required = false, name = "random", type = RandomLoadBalanceStrategy.class),
058            @XmlElement(required = false, name = "sticky", type = StickyLoadBalanceStrategy.class),
059            @XmlElement(required = false, name = "topic", type = TopicLoadBalanceStrategy.class)}
060            )
061        private LoadBalancerType loadBalancerType;
062    
063        public LoadBalanceType() {
064        }
065    
066        @Override
067        public String getShortName() {
068            return "loadbalance";
069        }
070    
071        public String getRef() {
072            return ref;
073        }
074    
075        public void setRef(String ref) {
076            this.ref = ref;
077        }
078    
079        public LoadBalancerType getLoadBalancerType() {
080            return loadBalancerType;
081        }
082    
083        public void setLoadBalancerType(LoadBalancerType loadbalancer) {
084            loadBalancerType = loadbalancer;
085        }
086    
087        protected Processor createOutputsProcessor(RouteContext routeContext, Collection<ProcessorType<?>> outputs)
088            throws Exception {
089            LoadBalancer loadBalancer = LoadBalancerType.getLoadBalancer(routeContext, loadBalancerType, ref);
090            for (ProcessorType processorType : outputs) {
091                // The outputs should be the SendProcessor
092                SendProcessor processor = (SendProcessor) processorType.createProcessor(routeContext);
093                loadBalancer.addProcessor(processor);
094            }
095            return loadBalancer;
096        }
097    
098        // when this method will be called
099        @Override
100        public Processor createProcessor(RouteContext routeContext) throws Exception {
101            LoadBalancer loadBalancer = LoadBalancerType.getLoadBalancer(routeContext, loadBalancerType, ref);
102            for (ProcessorType processorType : getOutputs()) {
103                // The outputs should be the SendProcessor
104                SendProcessor processor = (SendProcessor) processorType.createProcessor(routeContext);
105                loadBalancer.addProcessor(processor);
106            }
107    
108            return loadBalancer;
109        }
110    
111        // Fluent API
112        // -------------------------------------------------------------------------
113        public LoadBalanceType setLoadBalancer(LoadBalancer loadBalancer) {
114            loadBalancerType = new LoadBalancerType(loadBalancer);
115            return this;
116        }
117    
118        public LoadBalanceType roundRobin() {
119            loadBalancerType = new LoadBalancerType(new RoundRobinLoadBalancer());
120            return this;
121        }
122    
123        public LoadBalanceType random() {
124            loadBalancerType = new LoadBalancerType(new RandomLoadBalancer());
125            return this;
126        }
127    
128        public LoadBalanceType sticky(Expression<Exchange> correlationExpression) {
129            loadBalancerType = new LoadBalancerType(new StickyLoadBalancer(correlationExpression));
130            return this;
131        }
132    
133        public LoadBalanceType topic() {
134            loadBalancerType = new LoadBalancerType(new TopicLoadBalancer());
135            return this;
136        }
137    
138        @Override
139        public String getLabel() {
140            CollectionStringBuffer buffer = new CollectionStringBuffer();
141            List<ProcessorType<?>> list = getOutputs();
142            for (ProcessorType<?> processorType : list) {
143                buffer.append(processorType.getLabel());
144            }
145            return buffer.toString();
146        }
147    
148        @Override
149        public String toString() {
150            String result;
151            if (loadBalancerType != null) {
152                result = "LoadBalanceType[" + loadBalancerType + ", ";
153            } else {
154                result =  "LoadBalanceType[" + ref + ", ";
155            }
156            result = result + getOutputs() + "]";
157            return result;
158        }
159    
160    }