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Java > Open Source Codes > org > apache > ojb > odmg > ImplementationJTAImpl


1 package org.apache.ojb.odmg;
2
3 /* Copyright 2002-2005 The Apache Software Foundation
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17
18 import org.apache.ojb.broker.OJBRuntimeException;
19 import org.apache.ojb.broker.util.configuration.ConfigurationException;
20 import org.apache.ojb.broker.util.logging.Logger;
21 import org.apache.ojb.broker.util.logging.LoggerFactory;
22 import org.apache.ojb.odmg.oql.EnhancedOQLQuery;
23 import org.odmg.DArray;
24 import org.odmg.DBag;
25 import org.odmg.DList;
26 import org.odmg.DMap;
27 import org.odmg.DSet;
28 import org.odmg.Database;
29 import org.odmg.Implementation;
30 import org.odmg.Transaction;
31
32 /**
33  * Implementation of the ODMG {@link Implementation} interface for use in
34  * managed enviroments.
35  *
36  * @version $Id: ImplementationJTAImpl.java,v 1.2.2.3 2005/12/21 22:29:21 tomdz Exp $
37  */
38 public class ImplementationJTAImpl extends ImplementationImpl
39 {
40     private Logger log = LoggerFactory.getLogger(ImplementationJTAImpl.class);
41
42     protected ImplementationJTAImpl()
43     {
44         super();
45     }
46
47     public Database getDatabase(Object JavaDoc obj)
48     {
49         beginInternTransaction();
50         return this.getCurrentDatabase();
51     }
52
53     public Transaction currentTransaction()
54     {
55         beginInternTransaction();
56         /*
57         we wrap the intern odmg transaction to avoid unauthorised calls
58         since we use proprietary extensions for Transaction interface
59         do cast to enhanced interface
60         */
61         return new NarrowTransaction((TransactionImpl) super.currentTransaction());
62     }
63
64     public EnhancedOQLQuery newOQLQuery()
65     {
66         beginInternTransaction();
67         return super.newOQLQuery();
68     }
69
70     public DList newDList()
71     {
72         beginInternTransaction();
73         return super.newDList();
74     }
75
76     public DBag newDBag()
77     {
78         beginInternTransaction();
79         return super.newDBag();
80     }
81
82     public DSet newDSet()
83     {
84         beginInternTransaction();
85         return super.newDSet();
86     }
87
88     public DArray newDArray()
89     {
90         beginInternTransaction();
91         return super.newDArray();
92     }
93
94     public DMap newDMap()
95     {
96         beginInternTransaction();
97         return super.newDMap();
98     }
99
100     /**
101      * Here we start a intern odmg-Transaction to hide transaction demarcation
102      * This method could be invoked several times within a transaction, but only
103      * the first call begin a intern odmg transaction
104      */
105     private void beginInternTransaction()
106     {
107         if (log.isDebugEnabled()) log.debug("beginInternTransaction was called");
108         J2EETransactionImpl tx = (J2EETransactionImpl) super.currentTransaction();
109         if (tx == null) tx = newInternTransaction();
110         if (!tx.isOpen())
111         {
112             // start the transaction
113 tx.begin();
114             tx.setInExternTransaction(true);
115         }
116     }
117
118     /**
119      * Returns a new intern odmg-transaction for the current database.
120      */
121     private J2EETransactionImpl newInternTransaction()
122     {
123         if (log.isDebugEnabled()) log.debug("obtain new intern odmg-transaction");
124         J2EETransactionImpl tx = new J2EETransactionImpl(this);
125         try
126         {
127             getConfigurator().configure(tx);
128         }
129         catch (ConfigurationException e)
130         {
131             throw new OJBRuntimeException("Cannot create new intern odmg transaction", e);
132         }
133         return tx;
134     }
135
136     /**
137      * Not supported in managed-environment.
138      */
139     public Transaction newTransaction()
140     {
141         throw new UnsupportedOperationException JavaDoc("Not supported in managed environment");
142     }
143 }
144
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