The design and implementation of the "API" framework in the Java class library

The design and implementation of the design and implementation technical principles of the "transaction API" framework in the Java class library introduction: When it comes to database operation, transaction management is very important.The transaction ensures the consistency and integrity of the database operation, and can roll back the failure operation or submit a successful operation.In the Java library, we can use the "Affairs API" framework to manage affairs.This article will introduce the design and implementation of the framework of the framework, and provide relevant Java code examples. 1. The concept of transaction Affairs is a collection of database operations, and they are either successfully executed or rolled back.One transaction has the following four characteristics (or called ACID features): 1. Atomicity: The operation in the transaction is either successfully implemented or rolled back, and there is no part of the successful part of the rollback. 2. consistency: Before and after the start of the transaction, the database must be consistent, that is, to meet the pre -defined constraint conditions. 3. Isolation: Affairs of concurrent execution should be separated from each other and do not interfere with each other. 4. Durability: Once the transaction is submitted, the result should be permanently stored in the database, and it will not be lost even if the system failure occurs. 2. The technical principle of implementation of transaction management The "transaction API" framework in the Java class library is based on the following three core concepts to implement the management of transactions: connection, saving point, and rollback. 1. Connection: Connection represents interactive channels with the database, which can execute SQL statements and manage affairs.In the Java class library, we can use the `java.sql.connection` interface to represent the database connection object. 2. Savepoint: The saving point is a mark in the transaction to identify a specific operating point.During the execution of transactions, we can create multiple saving points and then roll back to a specified savings point.In the Java class library, we can use the `java.sql.savepoint` interface to create and manage the preservation point. Below is an example of a Java code that creates a saved point: try { // Get the connection object Connection connection = dataSource.getConnection(); // Open transaction connection.setAutoCommit(false); // Create the preservation point Savepoint savepoint = connection.setSavepoint(); // Execute some database operations // Roll back to the save point connection.rollback(savepoint); // Submit a transaction connection.commit(); } catch (SQLException e) { // Treatment abnormalities } finally { // Turn off the connection connection.close(); } 3. Rollback: Rolling refers to the revocation of all the operations in the transaction and returning to the state before the start of the transaction.In the Java class library, we can use the `rollback () method of the` java.sql.connection` interface to roll back and forth. The following is an example of Java code that rolls back. try { // Get the connection object Connection connection = dataSource.getConnection(); // Open transaction connection.setAutoCommit(false); // Execute some database operations // Abnormal, roll back the transaction connection.rollback(); } catch (SQLException e) { // Treatment abnormalities } finally { // Turn off the connection connection.close(); } 3. The design principle of transaction management The design of transaction management needs to consider the following aspects: 1. Boundary of Affairs: Determine the beginning and end of the affairs, and then perform the database operation within the scope of the transaction. 2. Abnormal treatment: If abnormalities occur during the transaction period, you need to roll back transactions and deal with abnormalities. 3. Access and release: The transaction management framework needs to provide the acquisition and release function of the connection object to ensure that the same connection is always used during the transaction period. 4. The creation and rollback of the preservation point: The transaction management framework needs to provide the creation and rollback function of the saving point. 5. Summary Affairs management is a very important part of the database operation.In the Java library, we can use the "Affairs API" framework to manage affairs.This article introduces the design and implementation of the framework, and provides related Java code examples.By using this framework reasonably, we can ensure the consistency and integrity of the database operation, and improve the stability and reliability of the system.