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.loadbalancer;
018
019
020
021 import java.util.List;
022
023 import javax.xml.bind.annotation.XmlAccessType;
024 import javax.xml.bind.annotation.XmlAccessorType;
025 import javax.xml.bind.annotation.XmlTransient;
026 import javax.xml.bind.annotation.XmlType;
027
028 import org.apache.camel.Exchange;
029 import org.apache.camel.Processor;
030 import org.apache.camel.impl.RouteContext;
031 import org.apache.camel.model.IdentifiedType;
032 import org.apache.camel.processor.loadbalancer.LoadBalancer;
033 import org.apache.camel.util.IntrospectionSupport;
034 import org.apache.camel.util.ObjectHelper;
035 import static org.apache.camel.util.ObjectHelper.notNull;
036
037 @XmlType(name = "loadBalancerType")
038 @XmlAccessorType(XmlAccessType.FIELD)
039 public class LoadBalancerType extends IdentifiedType implements LoadBalancer {
040
041 @XmlTransient
042 private LoadBalancer loadBalancer;
043 @XmlTransient
044 private String loadBalancerTypeName;
045
046 public LoadBalancerType() {
047 }
048
049 public LoadBalancerType(LoadBalancer loadBalancer) {
050 this.loadBalancer = loadBalancer;
051 }
052
053 protected LoadBalancerType(String loadBalancerTypeName) {
054 this.loadBalancerTypeName = loadBalancerTypeName;
055 }
056
057 public static LoadBalancer getLoadBalancer(RouteContext routeContext, LoadBalancerType type, String ref) {
058 if (type == null) {
059 notNull(ref, "ref or LoadBalancerType");
060 LoadBalancer loadBalancer = routeContext.lookup(ref, LoadBalancer.class);
061 if (loadBalancer instanceof LoadBalancerType) {
062 type = (LoadBalancerType) loadBalancer;
063 } else {
064 return loadBalancer;
065 }
066 }
067 return type.getLoadBalancer(routeContext);
068 }
069
070
071 /**
072 * Sets a named property on the data format instance using introspection
073 */
074 protected void setProperty(Object bean, String name, Object value) {
075 try {
076 IntrospectionSupport.setProperty(bean, name, value);
077 } catch (Exception e) {
078 throw new IllegalArgumentException("Failed to set property " + name + " on " + bean
079 + ". Reason: " + e, e);
080 }
081 }
082
083 /**
084 * Allows derived classes to customize the load balancer
085 */
086 protected void configureLoadBalancer(LoadBalancer loadBalancer) {
087 }
088
089 public LoadBalancer getLoadBalancer(RouteContext routeContext) {
090 if (loadBalancer == null) {
091 loadBalancer = createLoadBalancer(routeContext);
092 ObjectHelper.notNull(loadBalancer, "loadBalancer");
093 configureLoadBalancer(loadBalancer);
094 }
095 return loadBalancer;
096 }
097
098 /**
099 * Factory method to create the load balancer instance
100 */
101 protected LoadBalancer createLoadBalancer(RouteContext routeContext) {
102 if (loadBalancerTypeName != null) {
103 Class type = ObjectHelper.loadClass(loadBalancerTypeName, getClass().getClassLoader());
104 if (type == null) {
105 throw new IllegalArgumentException("The class " + loadBalancerTypeName + " is not on the classpath! Cannot use the loadBalancer " + this);
106 }
107 return (LoadBalancer) ObjectHelper.newInstance(type);
108 }
109 return null;
110 }
111
112
113 public void addProcessor(Processor processor) {
114 ObjectHelper.notNull(loadBalancer, "loadBalancer");
115 loadBalancer.addProcessor(processor);
116 }
117
118 public List<Processor> getProcessors() {
119 ObjectHelper.notNull(loadBalancer, "loadBalancer");
120 return loadBalancer.getProcessors();
121 }
122
123 public void removeProcessor(Processor processor) {
124 ObjectHelper.notNull(loadBalancer, "loadBalancer");
125 loadBalancer.removeProcessor(processor);
126 }
127
128 public void process(Exchange exchange) throws Exception {
129 ObjectHelper.notNull(loadBalancer, "loadBalancer");
130 loadBalancer.process(exchange);
131 }
132
133 }