1 package org.apache.onami.persist;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import javax.inject.Inject;
23 import javax.inject.Singleton;
24 import javax.persistence.EntityManager;
25
26 import static org.apache.onami.persist.Preconditions.checkNotNull;
27
28 /**
29 * Factory for transaction facades in case of JTA transactions.
30 */
31 @Singleton
32 class JtaTransactionFacadeFactory
33 implements TransactionFacadeFactory
34 {
35
36 /**
37 * The facade to the user transaction.
38 */
39 private final UserTransactionFacade utFacade;
40
41 /**
42 * Provider for the entity manager.
43 * The entity manager will be joined to the the transaction.
44 */
45 private final EntityManagerProvider emProvider;
46
47 /**
48 * Constructor.
49 *
50 * @param utFacade the user transaction facade.
51 * @param emProvider the entity manager provider.
52 */
53 @Inject
54 public JtaTransactionFacadeFactory( UserTransactionFacade utFacade, EntityManagerProvider emProvider )
55 {
56 this.utFacade = checkNotNull( utFacade, "utFacade is mandatory!" );
57 this.emProvider = checkNotNull( emProvider, "emProvider is mandatory!" );
58 }
59
60 /**
61 * {@inheritDoc}
62 */
63 // @Override
64 public TransactionFacade createTransactionFacade()
65 {
66 if ( utFacade.isActive() )
67 {
68 return new Inner( utFacade, emProvider.get() );
69 }
70 else
71 {
72 return new Outer( utFacade, emProvider.get() );
73 }
74 }
75
76 /**
77 * TransactionFacade representing an inner (nested) transaction. Starting and
78 * committing a transaction has no effect. This Facade will set the
79 * rollbackOnly flag on the underlying transaction in case of a rollback.
80 */
81 private static class Inner
82 implements TransactionFacade
83 {
84 private final UserTransactionFacade txn;
85
86 private final EntityManager em;
87
88 Inner( UserTransactionFacade txn, EntityManager em )
89 {
90 this.txn = checkNotNull( txn, "txn is mandatory!" );
91 this.em = checkNotNull( em, "em is mandatory!" );
92 }
93
94 /**
95 * {@inheritDoc}
96 */
97 // @Override
98 public void begin()
99 {
100 em.joinTransaction();
101 }
102
103 /**
104 * {@inheritDoc}
105 */
106 // @Override
107 public void commit()
108 {
109 // Do nothing
110 }
111
112 /**
113 * {@inheritDoc}
114 */
115 // @Override
116 public void rollback()
117 {
118 txn.setRollbackOnly();
119 }
120 }
121
122 /**
123 * TransactionFacade representing an outer transaction. This Facade starts
124 * and ends the transaction. If an inner transaction has set the rollbackOnly
125 * flag the transaction will be rolled back in any case.
126 */
127 private static class Outer
128 implements TransactionFacade
129 {
130 private final UserTransactionFacade txn;
131
132 private final EntityManager em;
133
134 Outer( UserTransactionFacade txn, EntityManager em )
135 {
136 this.txn = checkNotNull( txn, "txn is mandatory!" );
137 this.em = checkNotNull( em, "em is mandatory!" );
138 }
139
140 /**
141 * {@inheritDoc}
142 */
143 // @Override
144 public void begin()
145 {
146 txn.begin();
147 em.joinTransaction();
148 }
149
150 /**
151 * {@inheritDoc}
152 */
153 // @Override
154 public void commit()
155 {
156 if ( txn.getRollbackOnly() )
157 {
158 txn.rollback();
159 }
160 else
161 {
162 txn.commit();
163 }
164 }
165
166 /**
167 * {@inheritDoc}
168 */
169 // @Override
170 public void rollback()
171 {
172 txn.rollback();
173 }
174 }
175
176 }