Using Transactions in Java Programs

15.8.1 Problem

You want to perform a transaction in a JDBC script.

15.8.2 Solution

Use the standard JDBC transaction support mechanism.

15.8.3 Discussion

To perform transactions in Java, use your Connection object to turn off auto-commit mode. Then, after issuing your queries, use the object's commit( ) method to commit the transaction or rollback( ) to cancel it. Typically, you execute the statements for the transaction in a try block, with commit( ) at the end of the block. To handle failures, invoke rollback( ) in the corresponding exception handler:

try { conn.setAutoCommit (false); Statement s = conn.createStatement ( ); // move some money from one person to the other s.executeUpdate ("UPDATE money SET amt = amt - 6 WHERE name = 'Eve'"); s.executeUpdate ("UPDATE money SET amt = amt + 6 WHERE name = 'Ida'"); s.close ( ); conn.commit ( ); conn.setAutoCommit (true); } catch (SQLException e) { System.err.println ("Transaction failed, rolling back."); Cookbook.printErrorMessage (e); // empty exception handler in case rollback fails try { conn.rollback ( ); conn.setAutoCommit (true); } catch (Exception e2) { } }