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.lang.reflect.Method; 020import java.util.Map; 021import javax.xml.bind.annotation.XmlAccessType; 022import javax.xml.bind.annotation.XmlAccessorType; 023import javax.xml.bind.annotation.XmlAttribute; 024import javax.xml.bind.annotation.XmlRootElement; 025import javax.xml.bind.annotation.XmlTransient; 026 027import org.apache.camel.NoSuchBeanException; 028import org.apache.camel.Processor; 029import org.apache.camel.RuntimeCamelException; 030import org.apache.camel.Service; 031import org.apache.camel.processor.WrapProcessor; 032import org.apache.camel.spi.Metadata; 033import org.apache.camel.spi.Policy; 034import org.apache.camel.spi.RouteContext; 035import org.apache.camel.spi.TransactedPolicy; 036import org.apache.camel.util.CamelContextHelper; 037import org.apache.camel.util.ObjectHelper; 038import org.slf4j.Logger; 039import org.slf4j.LoggerFactory; 040 041/** 042 * Enables transaction on the route 043 * 044 * @version 045 */ 046@Metadata(label = "configuration") 047@XmlRootElement(name = "transacted") 048@XmlAccessorType(XmlAccessType.FIELD) 049public class TransactedDefinition extends OutputDefinition<TransactedDefinition> { 050 051 // TODO: Align this code with PolicyDefinition 052 053 // JAXB does not support changing the ref attribute from required to optional 054 // if we extend PolicyDefinition so we must make a copy of the class 055 @XmlTransient 056 public static final String PROPAGATION_REQUIRED = "PROPAGATION_REQUIRED"; 057 058 private static final Logger LOG = LoggerFactory.getLogger(TransactedDefinition.class); 059 060 @XmlTransient 061 protected Class<? extends Policy> type = TransactedPolicy.class; 062 @XmlAttribute 063 protected String ref; 064 @XmlTransient 065 private Policy policy; 066 067 public TransactedDefinition() { 068 } 069 070 public TransactedDefinition(Policy policy) { 071 this.policy = policy; 072 } 073 074 @Override 075 public String toString() { 076 String desc = description(); 077 if (ObjectHelper.isEmpty(desc)) { 078 return "Transacted"; 079 } else { 080 return "Transacted[" + desc + "]"; 081 } 082 } 083 084 protected String description() { 085 if (ref != null) { 086 return "ref:" + ref; 087 } else if (policy != null) { 088 return policy.toString(); 089 } else { 090 return ""; 091 } 092 } 093 094 @Override 095 public String getLabel() { 096 String desc = description(); 097 if (ObjectHelper.isEmpty(desc)) { 098 return "transacted"; 099 } else { 100 return "transacted[" + desc + "]"; 101 } 102 } 103 104 @Override 105 public boolean isAbstract() { 106 return true; 107 } 108 109 @Override 110 public boolean isTopLevelOnly() { 111 // transacted is top level as we only allow have it configured once per route 112 return true; 113 } 114 115 @Override 116 public boolean isWrappingEntireOutput() { 117 return true; 118 } 119 120 public String getRef() { 121 return ref; 122 } 123 124 public void setRef(String ref) { 125 this.ref = ref; 126 } 127 128 /** 129 * Sets a policy type that this definition should scope within. 130 * <p/> 131 * Is used for convention over configuration situations where the policy 132 * should be automatic looked up in the registry and it should be based 133 * on this type. For instance a {@link org.apache.camel.spi.TransactedPolicy} 134 * can be set as type for easy transaction configuration. 135 * <p/> 136 * Will by default scope to the wide {@link Policy} 137 * 138 * @param type the policy type 139 */ 140 public void setType(Class<? extends Policy> type) { 141 this.type = type; 142 } 143 144 /** 145 * Sets a reference to use for lookup the policy in the registry. 146 * 147 * @param ref the reference 148 * @return the builder 149 */ 150 public TransactedDefinition ref(String ref) { 151 setRef(ref); 152 return this; 153 } 154 155 @Override 156 public Processor createProcessor(RouteContext routeContext) throws Exception { 157 Policy policy = resolvePolicy(routeContext); 158 ObjectHelper.notNull(policy, "policy", this); 159 160 // before wrap 161 policy.beforeWrap(routeContext, this); 162 163 // create processor after the before wrap 164 Processor childProcessor = this.createChildProcessor(routeContext, true); 165 166 // wrap 167 Processor target = policy.wrap(routeContext, childProcessor); 168 169 if (!(target instanceof Service)) { 170 // wrap the target so it becomes a service and we can manage its lifecycle 171 target = new WrapProcessor(target, childProcessor); 172 } 173 return target; 174 } 175 176 protected Policy resolvePolicy(RouteContext routeContext) { 177 if (policy != null) { 178 return policy; 179 } 180 return doResolvePolicy(routeContext, getRef(), type); 181 } 182 183 protected static Policy doResolvePolicy(RouteContext routeContext, String ref, Class<? extends Policy> type) { 184 // explicit ref given so lookup by it 185 if (ObjectHelper.isNotEmpty(ref)) { 186 return CamelContextHelper.mandatoryLookup(routeContext.getCamelContext(), ref, Policy.class); 187 } 188 189 // no explicit reference given from user so we can use some convention over configuration here 190 191 // try to lookup by scoped type 192 Policy answer = null; 193 if (type != null) { 194 // try find by type, note that this method is not supported by all registry 195 Map<String, ?> types = routeContext.lookupByType(type); 196 if (types.size() == 1) { 197 // only one policy defined so use it 198 Object found = types.values().iterator().next(); 199 if (type.isInstance(found)) { 200 return type.cast(found); 201 } 202 } 203 } 204 205 // for transacted routing try the default REQUIRED name 206 if (type == TransactedPolicy.class) { 207 // still not found try with the default name PROPAGATION_REQUIRED 208 answer = routeContext.lookup(PROPAGATION_REQUIRED, TransactedPolicy.class); 209 } 210 211 // this logic only applies if we are a transacted policy 212 // still no policy found then try lookup the platform transaction manager and use it as policy 213 if (answer == null && type == TransactedPolicy.class) { 214 Class<?> tmClazz = routeContext.getCamelContext().getClassResolver().resolveClass("org.springframework.transaction.PlatformTransactionManager"); 215 if (tmClazz != null) { 216 // see if we can find the platform transaction manager in the registry 217 Map<String, ?> maps = routeContext.lookupByType(tmClazz); 218 if (maps.size() == 1) { 219 // only one platform manager then use it as default and create a transacted 220 // policy with it and default to required 221 222 // as we do not want dependency on spring jars in the camel-core we use 223 // reflection to lookup classes and create new objects and call methods 224 // as this is only done during route building it does not matter that we 225 // use reflection as performance is no a concern during route building 226 Object transactionManager = maps.values().iterator().next(); 227 LOG.debug("One instance of PlatformTransactionManager found in registry: {}", transactionManager); 228 Class<?> txClazz = routeContext.getCamelContext().getClassResolver().resolveClass("org.apache.camel.spring.spi.SpringTransactionPolicy"); 229 if (txClazz != null) { 230 LOG.debug("Creating a new temporary SpringTransactionPolicy using the PlatformTransactionManager: {}", transactionManager); 231 TransactedPolicy txPolicy = ObjectHelper.newInstance(txClazz, TransactedPolicy.class); 232 Method method; 233 try { 234 method = txClazz.getMethod("setTransactionManager", tmClazz); 235 } catch (NoSuchMethodException e) { 236 throw new RuntimeCamelException("Cannot get method setTransactionManager(PlatformTransactionManager) on class: " + txClazz); 237 } 238 ObjectHelper.invokeMethod(method, txPolicy, transactionManager); 239 return txPolicy; 240 } else { 241 // camel-spring is missing on the classpath 242 throw new RuntimeCamelException("Cannot create a transacted policy as camel-spring.jar is not on the classpath!"); 243 } 244 } else { 245 if (maps.isEmpty()) { 246 throw new NoSuchBeanException(null, "PlatformTransactionManager"); 247 } else { 248 throw new IllegalArgumentException("Found " + maps.size() + " PlatformTransactionManager in registry. " 249 + "Cannot determine which one to use. Please configure a TransactionTemplate on the transacted policy."); 250 } 251 } 252 } 253 } 254 255 return answer; 256 } 257 258}