The technical principles of Spring cache component in the Java library exploration

The technical principles of Spring cache component in the Java library exploration introduction: In modern software development, cache is widely used in many aspects, and is often used to improve application performance and reduce the number of access to databases or other external resources.The Spring framework provides a powerful cache component to simplify the use and management of cache.This article will explore the technical principles of the Spring cache component in the Java class library. 1. The basic concept of Spring cache component The Spring cache component is part of the Spring framework, which provides a mechanism for a statement to cache the result results in a statement.By adding a specific annotation to the method, we can cache the return value of the method and reuse the cache result when the method is subsequently called.This can significantly improve the performance of the application, especially when the execution cost of the method is relatively high, such as database queries and online access. 2. Principles of Spring cache component implementation The implementation of the Spring cache component is based on AOP (facing -oriented programming) ideas and dynamic proxy technology.When the method of calling the cache annotation is added, the cache notification generated by the Spring framework will be automatically triggered to find the result from the cache.If the result of the method in the cache is directly returned to the resulting party, saving the time and resource consumption of the execution method.If there is no result in the cache, continue to execute the method and cache the result so that the next call can be returned directly. Specifically, the technical principle of the implementation of the Spring cache component is as follows: 1. Cut surface: Spring realizes the cache function through AOP, decoupled the cache logic and business logic, so that the cache component can be easily applied to different business methods.The Spring framework automatically generates the cache notification according to the cache annotation, intercepting the method of cache annotation. 2. Dynamic proxy: Spring cache component depends on dynamic proxy technology, and generates proxy classes through dynamic proxy to enhance the target method.The proxy class will check whether there are results in the cache before the method execution, and determine whether the method is executed according to the situation.If there is a result in the cache, the agent class will directly return the cache result; if there is no result in the cache, the proxy class will execute the target method and cache the result. 3. Cache Manager: Spring cache component also depends on the cache manager to manage the cache.The cache manager is responsible for creating, searching, and deleting cache instances, and provides related operating interfaces.The Spring framework provides a variety of cache manager implementation, such as memory -based SimplecacheManager, Redis -based RedischeManager, etc. Developers can choose the appropriate cache manager according to actual needs. 3. Example of the use of Spring cache component The following example demonstrates how to use cache annotations in Spring to implement the cache of the method results. 1. Add the dependencies of adding Spring cache components to the pom.xml file: <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-cache</artifactId> </dependency> 2. Create a service class containing cache methods: @Service public class UserService { // Use @cacheable annotation to declare the result of the method that can be cached @Cacheable(value = "users", key = "#id") public User getUserById(String id) { // Query database or other resources to obtain user information // ... return user; } // Use @cacheevict annotation to declare that the method will empty the cache @CacheEvict(value = "users", key = "#id") public void deleteUserById(String id) { // Delete user information in the database // ... } } 3. Open the cache support in the main configuration file of the Spring: @Configuration @EnableCaching public class AppConfig { // Configure the cache manager @Bean public CacheManager cacheManager() { // Use memory -based cache manager SimpleCacheManager cacheManager = new SimpleCacheManager(); // Add the cache instance cacheManager.setCaches(Arrays.asList(new ConcurrentMapCache("users"))); return cacheManager; } } 4. Use the cache method: @Autowired private UserService userService; public void test() { // The first call will execute the method and cache the result User user = userService.getUserById("123"); // The second call, directly get the result from the cache, no execution method is required User cachedUser = userService.getUserById("123"); // Call the deletion method to clear the cache userService.deleteUserById("123"); } Through the above steps, we can easily use the Spring cache component to implement the cache of the method results.The Spring framework will be responsible for cache management, and developers only need to pay attention to the realization of business logic. in conclusion: This article analyzes the technical principles of the Spring cache component in the Java class library.This component can be achieved through AOP and dynamic proxy technology, which can effectively improve the performance of the application.Developers can declare the cache method that needs to be cached by adding an altitude betting solution, and use the appropriate cache manager to manage the cache.It is hoped that this article will help readers understand the principles and use of Spring cache components.