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.bam.processor; 018 019 import org.apache.camel.Exchange; 020 import org.apache.camel.Expression; 021 import org.apache.camel.Processor; 022 import org.apache.camel.bam.model.ProcessDefinition; 023 import org.apache.camel.bam.rules.ActivityRules; 024 import org.apache.camel.util.IntrospectionSupport; 025 import org.apache.commons.logging.Log; 026 import org.apache.commons.logging.LogFactory; 027 import org.springframework.orm.jpa.JpaTemplate; 028 import org.springframework.transaction.support.TransactionTemplate; 029 030 import java.util.List; 031 032 /** 033 * A base class for JPA based BAM which can use any entity to store the process 034 * instance information which allows derived classes to specialise the process 035 * instance entity. 036 * 037 * @version $Revision: $ 038 */ 039 public class JpaBamProcessorSupport<T> extends BamProcessorSupport<T> { 040 private static final transient Log LOG = LogFactory.getLog(JpaBamProcessorSupport.class); 041 042 private ActivityRules activityRules; 043 private JpaTemplate template; 044 private String findByKeyQuery; 045 private String keyPropertyName = "correlationKey"; 046 private boolean correlationKeyIsPrimary = true; 047 048 public JpaBamProcessorSupport(TransactionTemplate transactionTemplate, JpaTemplate template, Expression<Exchange> correlationKeyExpression, ActivityRules activityRules, Class<T> entitytype) { 049 super(transactionTemplate, correlationKeyExpression, entitytype); 050 this.activityRules = activityRules; 051 this.template = template; 052 } 053 054 public JpaBamProcessorSupport(TransactionTemplate transactionTemplate, JpaTemplate template, Expression<Exchange> correlationKeyExpression, ActivityRules activityRules) { 055 super(transactionTemplate, correlationKeyExpression); 056 this.activityRules = activityRules; 057 this.template = template; 058 } 059 060 public String getFindByKeyQuery() { 061 if (findByKeyQuery == null) { 062 findByKeyQuery = createFindByKeyQuery(); 063 } 064 return findByKeyQuery; 065 } 066 067 public void setFindByKeyQuery(String findByKeyQuery) { 068 this.findByKeyQuery = findByKeyQuery; 069 } 070 071 public ActivityRules getActivityRules() { 072 return activityRules; 073 } 074 075 public void setActivityRules(ActivityRules activityRules) { 076 this.activityRules = activityRules; 077 } 078 079 public String getKeyPropertyName() { 080 return keyPropertyName; 081 } 082 083 public void setKeyPropertyName(String keyPropertyName) { 084 this.keyPropertyName = keyPropertyName; 085 } 086 087 public JpaTemplate getTemplate() { 088 return template; 089 } 090 091 public void setTemplate(JpaTemplate template) { 092 this.template = template; 093 } 094 095 public boolean isCorrelationKeyIsPrimary() { 096 return correlationKeyIsPrimary; 097 } 098 099 public void setCorrelationKeyIsPrimary(boolean correlationKeyIsPrimary) { 100 this.correlationKeyIsPrimary = correlationKeyIsPrimary; 101 } 102 103 // Implementatiom methods 104 // ----------------------------------------------------------------------- 105 protected T loadEntity(Exchange exchange, Object key) { 106 T entity = findEntityByCorrelationKey(key); 107 if (entity == null) { 108 entity = createEntity(exchange, key); 109 setKeyProperty(entity, key); 110 ProcessDefinition definition = ProcessDefinition.getRefreshedProcessDefinition(template, getActivityRules().getProcessRules().getProcessDefinition()); 111 setProcessDefinitionProperty(entity, definition); 112 template.persist(entity); 113 114 // Now we must flush to avoid concurrent updates clashing trying to insert the 115 // same row 116 LOG.debug("About to flush on entity: " + entity + " with key: " + key); 117 template.flush(); 118 } 119 return entity; 120 } 121 122 protected T findEntityByCorrelationKey(Object key) { 123 if (isCorrelationKeyIsPrimary()) { 124 return template.find(getEntityType(), key); 125 } 126 else { 127 List<T> list = template.find(getFindByKeyQuery(), key); 128 if (list.isEmpty()) { 129 return null; 130 } 131 else { 132 return list.get(0); 133 } 134 } 135 } 136 137 /** 138 * Sets the key property on the new entity 139 */ 140 protected void setKeyProperty(T entity, Object key) { 141 IntrospectionSupport.setProperty(entity, getKeyPropertyName(), key); 142 } 143 144 protected void setProcessDefinitionProperty(T entity, ProcessDefinition processDefinition) { 145 IntrospectionSupport.setProperty(entity, "processDefinition", processDefinition); 146 } 147 148 /** 149 * Create a new instance of the entity for the given key 150 */ 151 protected T createEntity(Exchange exchange, Object key) { 152 return (T) exchange.getContext().getInjector().newInstance(getEntityType()); 153 } 154 155 protected void processEntity(Exchange exchange, T entity) throws Exception { 156 if (entity instanceof Processor) { 157 Processor processor = (Processor) entity; 158 processor.process(exchange); 159 } 160 else { 161 // TODO add other extension points - eg. passing in Activity 162 throw new IllegalArgumentException("No processor defined for this route"); 163 } 164 } 165 166 protected String createFindByKeyQuery() { 167 return "select x from " + getEntityType().getName() + " x where x." + getKeyPropertyName() + " = ?1"; 168 } 169 }