Analysis of the technical principle of Java Affairs API framework

Analysis of the technical principle of Java Affairs API framework The Java transaction API framework is an important tool for handling database transactions.It provides a simple and reliable way to manage and control the atomicity and consistency of multiple operations.This article will explore the technical principles of the Java transaction API framework and provide example code to help readers better understand. 1. The concept and characteristics of transaction Affairs refers to a group of operations, which are either successfully completed or rolled back to the original state.Affairs has four basic characteristics, namely atomics, consistency, isolation, and durability.The goal of the Java transaction API framework is to ensure that all operations meet these characteristics. Second, the composition of the Java transaction API framework Java Affairs API framework consists of the following core components: 1. Transaction Manager: Responsible for creating and managing affairs, providing methods such as starting affairs, submission of affairs, rollback transactions. 2. Transaction definition: Define the isolation level, timeout time, and only attributes of transaction. 3. Transaction State: records the current state of the transaction, such as whether it is submitted, whether it is rolling, etc. 4. Transaction Synchronization: It is used to perform additional operations when the transaction is completed, such as cleaning resources and sending messages. 5. Transaction Interceptor: Calling the transaction method, responsible for opening, submission and rollback transactions, and triggering the transaction synchronizer at appropriate time. 3. Java Affairs API framework workflow The workflow of the Java transaction API framework is as follows: 1. The first step is to configure the transaction manager and transaction definition.Usually, these configuration information is stored in the configuration file of the application. 2. When the application calls a method with transaction annotations, the transaction interceptor will intercept the call of the method and create a new transaction based on the definition of transaction. 3. The transaction interceptor will save the created transactions in the context of the current thread so that the subsequent operations can be obtained and using the transaction. 4. During the method execution, if an abnormalities occur, the transaction interceptor will roll back the transaction, otherwise it will continue to be executed. 5. When the method is executed, the transaction interceptor will determine whether to submit transactions or rollback transactions according to the execution result of the method. 6. If the transaction is submitted, the transaction interceptor will call the transaction manager's submission method to push all the operations of the transaction to the database. 7. If the transaction is rolled back, the transaction interceptor will call the rolling method of the transaction manager, revoke all operations and restore it to the original state. 8. After the transaction is completed, the operation of the transaction synchronizer will be executed when the transaction is completed, such as cleaning resources. Fourth, Java Affairs API framework for example code Below is a simple example code that demonstrates how to use the Java transaction API framework to handle database transactions: import javax.transaction.Transactional; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; @Service public class UserService { @Autowired private UserRepository userRepository; @Transactional public void createUser(String username, String password) { // Create a user User user = new User(username, password); userRepository.save(user); // Roll out the abnormalities manually, and the test transaction rolls back if (username.equals("admin")) { Throw New Runtimeexception ("The user name exists"); } } } In the above code, the `Createuser` method uses the`@transactional` annotation, indicating that this is a method that requires transaction management.When this method is called, if any abnormalities occur, transactions will be rolled back, and all executable database operations will be revoked. By using the Java transaction API framework, we can easily achieve complex transaction management logic and ensure the consistency and reliability of data. Summarize: This article introduces the technical principles of the Java transaction API framework and provides example code.The Java transaction API framework implements the management and control of transaction through core components such as transaction manager, transaction definition, transaction status, transaction synchronizer, and transaction interceptor.Using the Java transaction API framework, we can easily manage and control database transactions to ensure the consistency and reliability of data.