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 javax.xml.bind.annotation.XmlAccessType;
020 import javax.xml.bind.annotation.XmlAccessorType;
021 import javax.xml.bind.annotation.XmlAttribute;
022 import javax.xml.bind.annotation.XmlRootElement;
023 import javax.xml.bind.annotation.XmlTransient;
024
025 import org.apache.camel.Processor;
026 import org.apache.camel.Service;
027 import org.apache.camel.processor.WrapProcessor;
028 import org.apache.camel.spi.Policy;
029 import org.apache.camel.spi.RouteContext;
030 import org.apache.camel.spi.TransactedPolicy;
031 import org.apache.camel.util.ObjectHelper;
032
033 /**
034 * Represents an XML <policy/> element
035 *
036 * @version
037 */
038 @XmlRootElement(name = "policy")
039 @XmlAccessorType(XmlAccessType.FIELD)
040 public class PolicyDefinition extends OutputDefinition<PolicyDefinition> {
041
042 // TODO: Align this code with TransactedDefinition
043
044 @XmlTransient
045 protected Class<? extends Policy> type;
046 @XmlAttribute(required = true)
047 protected String ref;
048 @XmlTransient
049 private Policy policy;
050
051 public PolicyDefinition() {
052 }
053
054 public PolicyDefinition(Policy policy) {
055 this.policy = policy;
056 }
057
058 @Override
059 public String toString() {
060 return "Policy[" + description() + "]";
061 }
062
063 protected String description() {
064 if (policy != null) {
065 return policy.toString();
066 } else {
067 return "ref:" + ref;
068 }
069 }
070
071 @Override
072 public String getShortName() {
073 // a policy can be a hidden disguise for a transacted definition
074 boolean transacted = type != null && type.isAssignableFrom(TransactedPolicy.class);
075 return transacted ? "transacted" : "policy";
076 }
077
078 @Override
079 public String getLabel() {
080 return getShortName() + "[" + getDescription() + "]";
081 }
082
083 @Override
084 public boolean isAbstract() {
085 // policy should NOT be abstract
086 return false;
087 }
088
089 @Override
090 public boolean isTopLevelOnly() {
091 // a policy is often top-level but you can have it in lower-levels as well
092 return false;
093 }
094
095 public String getRef() {
096 return ref;
097 }
098
099 public void setRef(String ref) {
100 this.ref = ref;
101 }
102
103 /**
104 * Sets a policy type that this definition should scope within.
105 * <p/>
106 * Is used for convention over configuration situations where the policy
107 * should be automatic looked up in the registry and it should be based
108 * on this type. For instance a {@link org.apache.camel.spi.TransactedPolicy}
109 * can be set as type for easy transaction configuration.
110 * <p/>
111 * Will by default scope to the wide {@link Policy}
112 *
113 * @param type the policy type
114 */
115 public void setType(Class<? extends Policy> type) {
116 this.type = type;
117 }
118
119 /**
120 * Sets a reference to use for lookup the policy in the registry.
121 *
122 * @param ref the reference
123 * @return the builder
124 */
125 public PolicyDefinition ref(String ref) {
126 setRef(ref);
127 return this;
128 }
129
130 @Override
131 public Processor createProcessor(RouteContext routeContext) throws Exception {
132 Policy policy = resolvePolicy(routeContext);
133 ObjectHelper.notNull(policy, "policy", this);
134
135 // before wrap
136 policy.beforeWrap(routeContext, this);
137
138 // create processor after the before wrap
139 Processor childProcessor = this.createChildProcessor(routeContext, true);
140
141 // wrap
142 Processor target = policy.wrap(routeContext, childProcessor);
143
144 if (!(target instanceof Service)) {
145 // wrap the target so it becomes a service and we can manage its lifecycle
146 target = new WrapProcessor(target, childProcessor);
147 }
148 return target;
149 }
150
151 protected Policy resolvePolicy(RouteContext routeContext) {
152 if (policy != null) {
153 return policy;
154 }
155 // reuse code on transacted definition to do the resolution
156 return TransactedDefinition.doResolvePolicy(routeContext, getRef(), type);
157 }
158
159 }