JOTM :: CORE Framework's transaction rollback and recovery mechanism detailed explanation

JOTM (Java Open Transaction Manager) is a Java transaction manager that is used to handle transactions distributed on multiple databases.JOTM provides applications with a flexible and reliable transaction support, and ensures the consistency and reliability of transactions.In JOTM, transaction rolling and recovery mechanism plays a very important role. They help applications can run normally and maintain data consistency when facing errors or abnormalities. The transaction rollback means that after an error or abnormality occurs in a matter of a transaction, all the operations in the transaction are revoked or returned to the state before the error to maintain the consistency of the data.The rolling mechanism of transaction is one of the core functions in the JOTM framework. In JOTM, the transaction rollback mechanism is achieved through the following steps: 1. Registration resources: At the beginning of the transaction, the application needs to register the resources that require transaction management (such as database connections, message queues, etc.) to JOTM. 2. Starting transaction: Use JOTM's API to start a new transaction and get a transaction context. The context should be used for operational affairs. 3. Executive transaction operation: In the context of transaction, the application can perform a series of database operations or other business logic.These operations can be read, updated or deleted data. 4. Checkpoint management: When each checkpoint or important operation is completed, JOTM will save the status of the current transaction as a checkpoint so that the transaction can return to this state when the transaction is rolling. 5. Abnormal treatment: If errors or abnormalities occur during transaction execution, JOTM will roll back to the recent checkpoint and ensure that all transaction operations are revoked.This means that all operations on databases or other resources will be revoked to maintain data consistency. 6. Submission of transaction: If the transaction is successfully executed and no error occurs, JOTM will submit the transaction and save the results of all operations permanently into the database or other resources. The above is the basic step of the rolling mechanism of the transaction.The JOTM framework provides many APIs and configuration options to enable developers to control the rolling and recovery of transactions more flexibly.Here are some commonly used programming code and related configuration examples: 1. Registration resources: Jotm jotm = new Jotm(true, false); UserTransaction ut = jotm.getUserTransaction(); ut.begin(); // Register a database connection resource Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb", "username", "password"); jotm.getResourceFactory().registerResource(connection); // Register other resources 2. Executive transaction operation: ut.begin(); // Execute the database operation PreparedStatement statement = connection.prepareStatement("INSERT INTO users (name, age) VALUES (?, ?)"); statement.setString(1, "John"); statement.setInt(2, 25); statement.executeUpdate(); // Execute other business logic ut.commit(); 3. Configure JOTM: The configuration can be configured using the configuration file or programming method of the JOTM.The following is a sample configuration file (JOTM.PROPERTIES): TransactionManager.Factory=org.objectweb.jotm.Current UserTransaction.Factory=org.objectweb.jotm.UserTransactionFactory # More configuration options Through the above configuration files, you can specify the factory category of the transaction manager and user affairs used by JOTM. In summary, JOTM's transaction rollback and recovery mechanism is a key link to ensure the consistency and reliability of distributed transactions.Through reasonable programming and configuration, developers can flexibly control the rolling and recovery of transactions to ensure that the application can run and maintain the consistency of data normally when errors or abnormalities occur.