Discover the principles and implementation of Spring Cache technology in the Java class library

Spring Cache technology is a very important component in Spring Framework. It can provide a simple and effective data cache function to improve the performance and response speed of the application.This article will explore the principles and implementation methods of Spring Cache technology in the Java class library, and provide some Java code examples. 1. Principles of Spring Cache Technology Before discussing the principle of Spring Cache technology, first understand what cache is.The cache is a copy of the data stored in a high -speed random access memory. When the application needs to access these data, it can be obtained directly from the cache instead of obtaining from slower data sources (such as databases).Therefore, by using the cache, the number of access to the underlying data source can be reduced and the system performance can be improved. Spring Cache technology is based on the cache interface Javax.cache in the Java standard library, but it is expanded and encapsulated on its basis, providing a more friendly and powerful cache function.It caches the return result of the method by annotating, and controls the effectiveness of the cache according to certain strategies (such as cache expiration time, cache's update strategy, etc.). The implementation principle of Spring Cache technology mainly includes the following points: 1. CacheManager: Used to manage cache objects.The Spring framework provides a variety of cache managers, including memory -based cache, cache -based cache, EHCACHE -based cache, etc. 2. Cache Annotion: Methods for identifying the need to perform cache operations.The Spring framework provides multiple caching solutions, including@cacheable,@cachepput,@cacheEvick, etc.By adding these annotations to the method, the rules and behaviors of the cache can be specified. 3. Key Generator: Used to generate unique cache keys.In Spring Cache technology, the cache key is usually dynamically generated by the method parameters, so a cache key generator needs to generate a unique cache key to facilitate distinction of different cache results. 4. Cache Interceptor: Used to intercept the call of the cache method. According to the cache injection solution and cache key generator, determine whether to obtain data from the cache or directly call the original method and cache the result. Second, the implementation of Spring Cache technology Below a simple example to illustrate the implementation of Spring Cache technology.Suppose there is a UserService class that contains a way to get user information GetuserByid. @Service public class UserService { @Cacheable(value = "userCache", keyGenerator = "customKeyGenerator") public User getUserById(Long userId) { // Eliminate the code of querying user information from the database return userRepository.findById(userId).orElse(null); } } In this example, the GetuserByid method needs to be cached through the @Cacheable annotation.The value attribute in the annotation specifies the name of the cache (usercache), and the keygenrator attribute specifies the CustomKenrator of CustomKENARTOR. The implementation method of the cache key generator is as follows: @Component("customKeyGenerator") public class CustomKeyGenerator implements KeyGenerator { @Override public Object generate(Object target, Method method, Object... params) { return method.getName() + Arrays.toString(params); } } In this example, the custom cache key generator uses the name and parameter list of the usage method as the cache key to ensure that the unique cache key is generated by different methods. Finally, you need to configure the cache manager in the configuration file of the Spring Boot application. yaml spring: cache: Type: Redis # cache manager type, can be EHCACHE, Redis, etc. In the above example, the type of cache manager is Redis, which can choose other cache managers according to actual needs. 3. Summary This article introduces the principles and implementation of Spring Cache technology in the Java class library.By using Spring Cache, you can easily add data cache functions to the application to improve the performance and response speed of the system.Through reasonable configuration of the cache manager, cache annotation, and cache key generator, more flexible and efficient cache strategies can be achieved.I hope that this article can understand Spring Cache technology and how to achieve cache function in the Java class library.