In -depth analysis of the JSR107 API and SPI framework in the Java class library
In -depth analysis of the JSR107 API and SPI framework in the Java class library
Overview:
The JSR107 in the Java class library is part of the Java specification. It defines a set of API interfaces for caching management, and a SPI (service provider interface) framework for realizing these interfaces.This article will in -depth analysis of the JSR107 API and SPI framework and discuss its application in Java development.
1. What is JSR107?
JSR107 is the number of Java Specification Requests, which defines a set of API interfaces for caching management.It is widely used in the cache implementation in Java applications, such as cache database query results in the web application or the result of remote calls in a distributed system.
2. JSR107 API：
JSR107 defines a set of standard cache management API interfaces for cache reading, writing and deleting operations.Here are some core interfaces and methods:
-CACHE: indicates a cache instance.Can be obtained through cachmanager.
-Cachemanager: The container that manages the cache instance.You can create, obtain and delete the cache through this interface.
-Cacheconfiguration: The collection of cache configuration items.It is used to set the cache parameters, such as expiration time, maximum cache size.
-CacheEntryListener: Used to monitor the changes in the entry of the cache, such as the creation, update and deleting.
-Cacheloader: The callback interface for loading the data when the cache is cached.
-Cachewriter: The recovery interface used to persist data during cache updates.
The following is an example of a simple use of the JSR107 API:
import javax.cache.Cache;
import javax.cache.CacheManager;
import javax.cache.Caching;
import javax.cache.configuration.MutableConfiguration;
public class Jsr107Example {
public static void main(String[] args) {
// Create a cache manager
CacheManager cacheManager = Caching.getCachingProvider().getCacheManager();
// Create a cache configuration item
MutableConfiguration<String, Integer> config = new MutableConfiguration<>();
config.setTypes(String.class, Integer.class);
// Create a cache instance
Cache<String, Integer> cache = cacheManager.createCache("myCache", config);
// Add entries to the cache
cache.put("key", 123);
// Get the entry from the cache
Integer value = cache.get("key");
System.out.println (value); // Output: 123
}
}
3. JSR107 SPI framework:
The SPI framework of the JSR107 provides a way to achieve cache implementation through Java's ServiceLoader mechanism.It defines a set of interfaces to load and configure specific cache implementation.
The following is a simple SPI implementation example:
import javax.cache.configuration.Factory;
import javax.cache.expiry.Duration;
import javax.cache.expiry.ExpiryPolicy;
import java.util.concurrent.TimeUnit;
public class MyExpiryPolicyFactory implements Factory<ExpiryPolicy> {
@Override
public ExpiryPolicy create() {
return new MyExpiryPolicy();
}
public class MyExpiryPolicy implements ExpiryPolicy {
@Override
public Duration getExpiryForCreation() {
return new Duration(TimeUnit.SECONDS, 60);
}
@Override
public Duration getExpiryForAccess() {
return null;
}
@Override
public Duration getExpiryForUpdate() {
return null;
}
}
}
In the above examples, MyexpierPolicyFactory is a customized cache expiration strategy factory, which is used to provide custom expiration strategies.By customized Factory classes, the functions provided by the JSR107 API flexibly.
Summarize:
Through the introduction of this article, we learned about the JSR107 API and SPI framework in the Java class library.The JSR107 provides a standard cache management interface that allows Java applications to easily implement the cache function.At the same time, through the SPI framework, we can flexibly expand the function of the JSR107 and provide a custom cache implementation.In actual development, we can choose the appropriate cache implementation according to specific needs, and configure and expand it through the SPI.
