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This article introduces the relevant knowledge of "what is the JDBC transaction mechanism". In the operation of actual cases, many people will encounter such a dilemma. Next, let the editor lead you to learn how to deal with these situations. I hope you can read it carefully and be able to achieve something!

Transaction processing in Java

In general, J2EE application servers support JDBC transactions, JTA (Java Transaction API) transactions, and container-managed transactions. In general, * do not use the above three transaction types in your program at the same time, such as nesting JDBC transactions in JTA transactions. Second, transactions should be completed in the shortest possible time, and do not implement the use of transactions in different methods. Let's list two ways to handle JDBC transactions.

1. Use JDBC transaction processing in JavaBean

How do you combine multiple SQL statements into a single transaction in JDBC? In JDBC, when you open a connection object Connection, the default is auto-commit mode, and each SQL statement is treated as a transaction, that is, each time a statement is executed, the transaction is automatically confirmed. In order to combine multiple SQL statements into a single transaction, block the auto-commit schema. After the auto-commit mode is blocked, the SQL statement will not get JDBC transaction confirmation if the commit () method is not called. All SQL after the most recent call to the commit () method is confirmed when the method commit () is called.

Public int delete (int sID) {dbc = new DataBaseConnection (); Connection con = dbc.getConnection (); try {con.setAutoCommit (false); / / change the default commit mode of JDBC transactions dbc.executeUpdate ("delete from bylaw where ID=" + sID); dbc.executeUpdate ("delete from bylaw _ content where ID=" + sID); dbc.executeUpdate ("delete from bylaw _ affix where bylawid=" + sID); con.commit () / / commit JDBC transaction con.setAutoCommit (true); / / restore the default commit mode of JDBC transaction dbc.close (); return 1;} catch (Exception exc) {con.rollBack (); / / rollback JDBC transaction exc.printStackTrace (); dbc.close (); return-1;}}

2. JTA transaction in SessionBean

JTA is the J2EE solution for transaction services. In essence, it is part of a J2EE model that describes a transactional interface, such as the UserTransaction interface, which developers use directly or through the J2EE container to ensure that business logic runs reliably. The three main interfaces of JTA are UserTransaction interface, TransactionManager interface and Transaction interface. These interfaces share common transaction operations, such as commit () and rollback (), but also contain special transaction operations, such as suspend (), resume (), and enlist (), which appear only on specific interfaces to allow a certain degree of access control in the implementation. For example, UserTransaction can perform transaction demarcation and basic transaction operations, while TransactionManager can perform context management.

The application can call the UserTransaction.begin () method to start a transaction that is associated with the current thread in which the application is running. The underlying transaction manager actually handles the association between threads and transactions. The UserTransaction.commit () method terminates the transaction associated with the current thread. The UserTransaction.rollback () method discards the current transaction associated with the current thread.

Public int delete (int sID) {DataBaseConnection dbc = null; dbc = new DataBaseConnection (); dbc.getConnection (); UserTransaction transaction = sessionContext.getUserTransaction (); / / get JTA transaction try {transaction.begin (); / / start JTA transaction dbc.executeUpdate ("delete from bylaw where ID=" + sID); dbc.executeUpdate ("delete from bylaw _ content where ID=" + sID); dbc.executeUpdate ("delete from bylaw _ affix where bylawid=" + sID) Transaction.commit (); / / commit JTA transaction dbc.close (); return 1;} catch (Exception exc) {try {transaction.rollback (); / / JTA transaction rollback} catch (Exception ex) {/ / JTA transaction rollback error handling ex.printStackTrace ();} exc.printStackTrace (); dbc.close (); return-1 This is the end of the content of "what is the JDBC transaction mechanism". Thank you for your reading. If you want to know more about the industry, you can follow the website, the editor will output more high-quality practical articles for you!

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