How to use the Caffeine Cache framework in the Java class library

How to use the Caffeine Cache framework in the Java class library Introduction: Caffeine is a high -performance Java cache framework, which provides a simple and powerful way to improve the performance of the application.This article will introduce how to use the Caffeine cache framework and provide some Java code examples. Overview: Caches is a common mechanism that is used to reduce duplicate calculations and the frequency of data obtaining data from slow storage.Caffeine is an open source high -performance cache library that provides rich features such as automatic loading, expiration, asynchronous writing, etc.Using Caffeine, you can easily introduce cache into your Java application to optimize performance and reduce pressure on underlying resources.Here are some examples of using the caffine cache framework. 1. Add Caffeine dependencies First, you need to add caffeine dependencies to your project.You can add the following dependencies to Maven or Gradle configuration files: Maven： <dependency> <groupId>com.github.ben-manes.caffeine</groupId> <artifactId>caffeine</artifactId> <version>2.9.0</version> </dependency> Gradle： compile 'com.github.ben-manes.caffeine:caffeine:2.9.0' 2. Create a basic cache Next, you can create a basic cache object.The following is an example of creating cache using Caffeine: Cache<String, String> cache = Caffeine.newBuilder() .maximumSize(1000) .expireAfterWrite(10, TimeUnit.MINUTES) .build(); In the above example, we use the method of `Caffeine.newbuilder ()` to create a cache construct, and use a chain call to set the maximum size of the cache and the expiration time after being written. 3. Add and obtain data to the cache Once you create a cache object, you can use the `Put` method to put the data into the cache and use the` Get` method to obtain data from the cache.The following is an example: cache.put("key1", "value1"); String value = cache.get("key1"); System.out.println (value); // Output: Value1 In the above example, we put the key values on the cache `key1", "value1") `), and use the` Get` method to obtain the key to "key1". 4. Custom cache load Caffeine allows you to define a cache loader, and automatically loads the data when the data cannot be found in the cache.The following is an example: Cache<String, String> cache = Caffeine.newBuilder() .maximumSize(1000) .expireAfterWrite(10, TimeUnit.MINUTES) .build(key -> { // Live the logic of the data according to the key return loadValueFromDatabase(key); }); String value = cache.get("key2"); System.out.println (value); // Output: the value loaded from the database In the above example, we use the `build` method to convey a custom cache loader. It will not find the data when the data cannot find the data in the cache. Load the data from the database. 5. Cache Expired Strategy Using Caffeine, you can set an expired strategy of cache data.Here are some common expiration strategies: -Che expiration according to the time after writing: Cache<String, String> cache = Caffeine.newBuilder() .maximumSize(1000) .expireAfterWrite(10, TimeUnit.MINUTES) .build(); -Che expiration according to the time after the visit: Cache<String, String> cache = Caffeine.newBuilder() .maximumSize(1000) .expireAfterAccess(10, TimeUnit.MINUTES) .build(); -On customized expiration strategy: Cache<String, String> cache = Caffeine.newBuilder() .maximumSize(1000) .expireAfter(new Expiry<String, String>() { @Override public long expireAfterCreate(String key, String value, long currentTime) { // Return to the expiration time of the data return TimeUnit.MINUTES.toMillis(10); } @Override public long expireAfterUpdate(String key, String value, long currentTime, long currentDuration) { // Return to the expiration time of the data return currentDuration; } @Override public long expireAfterRead(String key, String value, long currentTime, long currentDuration) { // Return to the expiration time of the data return currentDuration; } }) .build(); In the above example, we use the `ExpireaFTERWRITE`,` ExpireaFTeraccess` and the custom `Expiry` interface to set different expiration strategies. Summarize: Caffeine is a powerful and easy -to -use Java cache framework.By using Caffeine, you can easily introduce the cache mechanism to improve the performance of the application.This article provides some basic usage and examples of Caffeine, which can be further studied and used according to specific needs.I hope this article will help you use the Caffeine Cache framework in the Java class library!