001 package org.apache.ojb.otm.transaction;
002
003 /* Copyright 2003-2005 The Apache Software Foundation
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * 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
018 import org.apache.ojb.broker.PBKey;
019 import org.apache.ojb.otm.OTMConnection;
020 import org.apache.ojb.otm.core.BaseConnection;
021 import org.apache.ojb.otm.core.Transaction;
022 import org.apache.ojb.otm.core.TransactionException;
023
024 import java.util.HashMap;
025
026 /**
027 *
028 * Factory for local transactions. Each OTMConnection is associated with exactly one transaction.
029 *
030 * @author <a href="mailto:rraghuram@hotmail.com">Raghu Rajah</a>
031 *
032 */
033 public class LocalTransactionFactory implements TransactionFactory
034 {
035
036 private HashMap _transactionMap;
037
038 public LocalTransactionFactory ()
039 {
040 _transactionMap = new HashMap();
041 }
042
043 /**
044 * @see org.apache.ojb.otm.transaction.TransactionFactory#getTransactionForConnection(OTMConnection)
045 */
046 public Transaction getTransactionForConnection (OTMConnection connection)
047 {
048 if (!(connection instanceof BaseConnection))
049 {
050 StringBuffer msg = new StringBuffer();
051 msg.append("Unknown connection type: ");
052 if (connection != null)
053 msg.append(connection.getClass().getName());
054 else
055 msg.append(" null. Make sure you pass a non-null OTMConnection to this method. An OTMConnection can be acquired by calling acquireConnection (PBKey pbKey)");
056 throw new TransactionFactoryException(msg.toString());
057 }
058
059 Transaction tx = (Transaction) _transactionMap.get(connection);
060 if (tx == null)
061 {
062 tx = new Transaction();
063 _transactionMap.put(connection, tx);
064 }
065 // ensure that this connection is registered into this transaction
066 tx.registerConnection(connection);
067 return tx;
068 }
069
070
071 /**
072 * @see org.apache.ojb.otm.transaction.TransactionFactory#acquireConnection(PBKey)
073 */
074 public OTMConnection acquireConnection (PBKey pbKey)
075 {
076 OTMConnection newConnection = new LocalConnection(pbKey);
077 // Ensure the transaction is established for this connection.
078 getTransactionForConnection(newConnection);
079 return newConnection;
080 }
081
082 /**
083 *
084 * Represents a local connection. This is a private static inner class to restrict visibility
085 * to others.
086 *
087 * @author <a href="mailto:rraghuram@hotmail.com">Raghu Rajah</a>
088 *
089 */
090 private static class LocalConnection extends BaseConnection
091 {
092 public LocalConnection (PBKey pbKey)
093 {
094 super(pbKey);
095 }
096
097
098 /**
099 * @see org.apache.ojb.otm.core.BaseConnection#transactionBegin()
100 */
101 public void transactionBegin() throws TransactionException
102 {
103 getKernelBroker().beginTransaction();
104 }
105
106 /**
107 * @see org.apache.ojb.otm.core.BaseConnection#transactionPrepare()
108 */
109 public void transactionPrepare() throws TransactionException
110 {
111 // Nothing to do!
112 }
113
114 /**
115 * @see org.apache.ojb.otm.core.BaseConnection#transactionCommit()
116 */
117 public void transactionCommit() throws TransactionException
118 {
119 getKernelBroker().commitTransaction();
120 }
121
122 /**
123 * @see org.apache.ojb.otm.core.BaseConnection#transactionRollback()
124 */
125 public void transactionRollback() throws TransactionException
126 {
127 getKernelBroker().abortTransaction();
128 }
129
130 }
131 }