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1   /*
2    * Copyright 2001-2004 The Apache Software Foundation.
3    * 
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    * 
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    * 
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  package org.apache.juddi.util.jdbc;
17  
18  import java.sql.Connection;
19  import java.sql.SQLException;
20  import java.util.Vector;
21  
22  /***
23   * Transaction txn = new Transaction();
24   * txn.begin(conn1);
25   * txn.begin(conn2);
26   * txn.begin(conn3);
27   * txn.commit();
28   * txn.rollback();
29   *
30   * @author  Graeme Riddell
31   */
32  public class Transaction
33  {
34    /***
35     * Vector of all connections involved in this transaction
36     */
37    private Vector vect = null;
38  
39    /***
40     * default constructor
41     */
42    public Transaction()
43    {
44      this.vect = new Vector();
45    }
46  
47    /***
48     * If the connection is known then do nothing. If the connection is
49     * new then issue a SQL begin work and hold onto it for later. Actually the
50     * begin work is implicit and autocommit drives whether a transaction is
51     * progressed.
52     */
53    public void begin(Connection conn)
54      throws SQLException
55    {
56      // make sure auto commit is disabled
57      if (conn.getAutoCommit() == true)
58        conn.setAutoCommit(false);
59  
60      // If this connection has already been begun then
61      // just return to the caller. Nothing more to do.
62      for (int i=0; i<vect.size(); i++)
63      {
64        if ((Connection)(vect.elementAt(i)) == conn)
65          return;
66      }
67  
68      // add new connection to the collection
69      vect.add(conn);
70    }
71  
72   /***
73    * commit on all connections. This is not XA, but it could be one day.
74    */
75    public void commit()
76      throws SQLException
77    {
78      // loop through all connections and commit them
79      for (int i=0; i<vect.size(); i++)
80      {
81        Connection conn = (Connection)vect.elementAt(i);
82        conn.commit();
83      }
84  
85      // they're all committed, now let's discard them
86      vect.removeAllElements();
87    }
88  
89   /***
90    * rollback on all connections. This is not XA, but it could be one day.
91    */
92    public void rollback()
93      throws SQLException
94    {
95      // loop through all collections and roll them back
96      for (int i=0; i<vect.size(); i++)
97      {
98        Connection conn = (Connection)vect.elementAt(i);
99        conn.rollback();
100     }
101 
102     // they're all rolled back, now let's discard them
103     vect.removeAllElements();
104   }
105 }