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.model; 018 019import java.util.Map; 020import javax.xml.bind.annotation.XmlAccessType; 021import javax.xml.bind.annotation.XmlAccessorType; 022import javax.xml.bind.annotation.XmlAnyAttribute; 023import javax.xml.bind.annotation.XmlTransient; 024import javax.xml.bind.annotation.XmlType; 025import javax.xml.namespace.QName; 026 027import org.apache.camel.processor.loadbalancer.LoadBalancer; 028import org.apache.camel.spi.Metadata; 029import org.apache.camel.spi.RouteContext; 030import org.apache.camel.util.IntrospectionSupport; 031import org.apache.camel.util.ObjectHelper; 032 033/** 034 * Balances message processing among a number of nodes 035 */ 036@Metadata(label = "eip,routing") 037@XmlType(name = "loadBalancer") 038@XmlAccessorType(XmlAccessType.FIELD) 039public class LoadBalancerDefinition extends IdentifiedType implements OtherAttributesAware { 040 @XmlTransient 041 private LoadBalancer loadBalancer; 042 @XmlTransient 043 private String loadBalancerTypeName; 044 // use xs:any to support optional property placeholders 045 @XmlAnyAttribute 046 private Map<QName, Object> otherAttributes; 047 048 public LoadBalancerDefinition() { 049 } 050 051 public LoadBalancerDefinition(LoadBalancer loadBalancer) { 052 this.loadBalancer = loadBalancer; 053 } 054 055 protected LoadBalancerDefinition(String loadBalancerTypeName) { 056 this.loadBalancerTypeName = loadBalancerTypeName; 057 } 058 059 /** 060 * Sets a named property on the data format instance using introspection 061 */ 062 protected void setProperty(Object bean, String name, Object value) { 063 try { 064 IntrospectionSupport.setProperty(bean, name, value); 065 } catch (Exception e) { 066 throw new IllegalArgumentException("Failed to set property " + name + " on " + bean + ". Reason: " + e, e); 067 } 068 } 069 070 /** 071 * Maximum number of outputs, as some load balancers only support 1 processor 072 */ 073 protected int getMaximumNumberOfOutputs() { 074 return Integer.MAX_VALUE; 075 } 076 077 /** 078 * Allows derived classes to customize the load balancer 079 */ 080 protected void configureLoadBalancer(LoadBalancer loadBalancer) { 081 } 082 083 public LoadBalancer getLoadBalancer(RouteContext routeContext) { 084 return loadBalancer; 085 } 086 087 public void setLoadBalancer(LoadBalancer loadBalancer) { 088 this.loadBalancer = loadBalancer; 089 } 090 091 @Override 092 public Map<QName, Object> getOtherAttributes() { 093 return otherAttributes; 094 } 095 096 @Override 097 public void setOtherAttributes(Map<QName, Object> otherAttributes) { 098 this.otherAttributes = otherAttributes; 099 } 100 101 /** 102 * Factory method to create the load balancer from the loadBalancerTypeName 103 */ 104 protected LoadBalancer createLoadBalancer(RouteContext routeContext) { 105 ObjectHelper.notEmpty(loadBalancerTypeName, "loadBalancerTypeName", this); 106 107 LoadBalancer answer = null; 108 if (loadBalancerTypeName != null) { 109 Class<?> type = routeContext.getCamelContext().getClassResolver().resolveClass(loadBalancerTypeName, LoadBalancer.class); 110 if (type == null) { 111 throw new IllegalArgumentException("Cannot find class: " + loadBalancerTypeName + " in the classpath"); 112 } 113 answer = (LoadBalancer) routeContext.getCamelContext().getInjector().newInstance(type); 114 configureLoadBalancer(answer); 115 } 116 117 return answer; 118 } 119 120 @Override 121 public String toString() { 122 if (loadBalancer != null) { 123 return loadBalancer.toString(); 124 } else { 125 return loadBalancerTypeName; 126 } 127 } 128}