1 //----------------------------------------------------------------------
2 //
3 // PerfectJPattern: "Design patterns are good but components are better!"
4 // JtaTransactionStrategy.java Copyright (c) 2009 Giovanni Azua Garcia
5 // bravegag@hotmail.com
6 //
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License
9 // as published by the Free Software Foundation; either version 3
10 // of the License, or (at your option) any later version.
11 //
12 // This program is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
16 //
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, see <http://www.gnu.org/licenses/>.
19 //
20 //----------------------------------------------------------------------
21 package org.perfectjpattern.jee.integration.dao;
22
23 import javax.transaction.*;
24
25 import org.apache.commons.lang.*;
26 import org.perfectjpattern.core.api.structural.adapter.*;
27 import org.perfectjpattern.core.structural.adapter.*;
28 import org.perfectjpattern.jee.api.business.servicelocator.*;
29 import org.perfectjpattern.jee.api.integration.dao.*;
30 import org.perfectjpattern.jee.business.servicelocator.*;
31
32 /**
33 * Concrete implementation of {@link ITransactionStrategy} targeting the
34 * use of {@link UserTransaction}
35 *
36 * @author <a href="mailto:bravegag@hotmail.com">Giovanni Azua</a>
37 * @version $Revision: 1.0 $Date: Feb 19, 2009 1:51:31 PM $
38 */
39 public
40 class JtaTransactionStrategy
41 implements ITransactionStrategy
42 {
43 //------------------------------------------------------------------------
44 // public
45 //------------------------------------------------------------------------
46 /**
47 * Constructs a {@link JtaTransactionStrategy} using the default
48 * UserTransaction service name "java:comp/UserTransaction"
49 */
50 public
51 JtaTransactionStrategy()
52 {
53 this("java:comp/UserTransaction");
54 }
55
56 //------------------------------------------------------------------------
57 /**
58 * Constructs a {@link JtaTransactionStrategy} from the UserTransaction
59 * service name provided. It can be server-specific.
60 *
61 * @param aServiceName The Service name
62 * @throws IllegalArgumentException 'aServiceName' must not be null
63 */
64 public
65 JtaTransactionStrategy(String aServiceName)
66 throws IllegalArgumentException
67 {
68 Validate.notNull(aServiceName, "'aServiceName' must not be null");
69
70 theServiceName = aServiceName;
71 }
72
73 //------------------------------------------------------------------------
74 /**
75 * {@inheritDoc}
76 */
77 public ITransaction
78 getTransaction()
79 {
80 IServiceLocator myServiceLocator = ServiceLocator.getInstance();
81
82 UserTransaction myUserTransaction = myServiceLocator.locate(
83 theServiceName);
84
85 if (theTransactionAdapter == null || theTransactionAdapter.
86 getAdaptee() != myUserTransaction)
87 {
88 theTransactionAdapter = new Adapter<ITransaction, UserTransaction>(
89 ITransaction.class, myUserTransaction);
90 }
91
92 return theTransactionAdapter.getTarget();
93 }
94
95 //------------------------------------------------------------------------
96 // members
97 //------------------------------------------------------------------------
98 private final String theServiceName;
99 private IAdapter<ITransaction, UserTransaction> theTransactionAdapter;
100 }