spring-boot中配置和使用Caffeine Cache

本地缓存，之前一直用Guava Cache，最近spring-boot推荐使用Caffeine Cache。
主要的三种本地缓存性能对比：


简单几步，就可以在spring-boot中配置和使用Caffeine Cache：

1、引入依赖：

<!-- local cache --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-cache</artifactId></dependency><dependency><groupId>com.github.ben-manes.caffeine</groupId><artifactId>caffeine</artifactId></dependency>

2、配置：
有两种方法：
- application.yml配置文件中配置：
  - 优点：简单
  - 缺点：无法针对每个cache配置不同的参数，比如过期时长、最大容量
- 配置类中配置
  - 优点：可以针对每个cache配置不同的参数，比如过期时长、最大容量
  - 缺点：要写一点代码

2.1、配置文件中直接配置：

spring:  cache:    type: CAFFEINE    cache-names:      - getPersonById      - name2    caffeine:      spec: maximumSize=500,expireAfterWrite=5s

然后还要在主类中加上@EnableCaching注解：

@SpringBootApplication@EnableScheduling@EnableCachingpublic class MySpringBootApplication

2.2、另外一种更灵活的方法是在配置类中配置：

package com.xjj.config;import java.util.ArrayList;import java.util.concurrent.TimeUnit;import org.springframework.cache.CacheManager;import org.springframework.cache.annotation.EnableCaching;import org.springframework.cache.caffeine.CaffeineCache;import org.springframework.cache.support.SimpleCacheManager;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.context.annotation.Primary;import com.github.benmanes.caffeine.cache.Caffeine;/** * Cache配置類，用于缓存数据 * @author XuJijun * */@Configuration@EnableCachingpublic class CacheConfig {public static final int DEFAULT_MAXSIZE = 50000;public static final int DEFAULT_TTL = 10;/** * 定義cache名稱、超時時長（秒）、最大容量 * 每个cache缺省：10秒超时、最多缓存50000条数据，需要修改可以在构造方法的参数中指定。 */public enum Caches{getPersonById(5), //有效期5秒getSomething, //缺省10秒getOtherthing(300, 1000), //5分钟，最大容量1000;Caches() {}Caches(int ttl) {this.ttl = ttl;}Caches(int ttl, int maxSize) {this.ttl = ttl;this.maxSize = maxSize;}private int maxSize=DEFAULT_MAXSIZE;//最大數量private int ttl=DEFAULT_TTL;//过期时间（秒）public int getMaxSize() {return maxSize;}public int getTtl() {return ttl;}}/** * 创建基于Caffeine的Cache Manager * @return */@Bean@Primarypublic CacheManager caffeineCacheManager() {SimpleCacheManager cacheManager = new SimpleCacheManager();ArrayList<CaffeineCache> caches = new ArrayList<CaffeineCache>();for(Caches c : Caches.values()){caches.add(new CaffeineCache(c.name(), Caffeine.newBuilder().recordStats().expireAfterWrite(c.getTtl(), TimeUnit.SECONDS).maximumSize(c.getMaxSize()).build()));}cacheManager.setCaches(caches);return cacheManager;}}

3、代码中使用：

package com.xjj.service;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.cache.annotation.Cacheable;import org.springframework.stereotype.Service;import com.xjj.dao.PersonDAO;import com.xjj.entity.Person;@Servicepublic class PersonService {protected final Logger logger = LoggerFactory.getLogger(this.getClass());@Autowiredprivate PersonDAO personDao;/** * 根据id获取Person对象，使用缓存 * @param id * @return Person对象 */@Cacheable(value="getPersonById", sync=true)public Person getPersonById(int id){logger.debug("getting data from database, personId={}", id);return personDao.getPersonById(id);}}

4、测试：

@AutowiredPersonService personService;@Testpublic void localCacheTest() throws JsonProcessingException, InterruptedException{System.out.println("第一次："); //从数据库中获取Person p = personService.getPersonById(2);logger.info("1st time: {}", objectMapper.writeValueAsString(p));System.out.println("第二次："); //从缓存中获取p = personService.getPersonById(2);logger.info("2nd time: {}", objectMapper.writeValueAsString(p));Thread.sleep(5000);System.out.println("第三次："); //5秒钟超时后，从数据库中获取p = personService.getPersonById(2);logger.info("3rd time: {}", objectMapper.writeValueAsString(p));System.out.println("第四次："); //从缓存中获取p = personService.getPersonById(2);logger.info("4th time: {}", objectMapper.writeValueAsString(p));}

测试结果：

第一次：2016-11-02 17:11:13,105:DEBUG main (PersonService.java:27) - getting data from database, personId=22016-11-02 17:11:13,150:INFO main (HikariDataSource.java:93) - HikariPool-1 - Started.2016-11-02 17:11:13,523:DEBUG main (BaseJdbcLogger.java:145) - ==>  Preparing: SELECT id, first_name AS firstName, last_name AS lastName, birth_date AS birthDate, sex, phone_no AS phoneNo FROM test.t_person WHERE id=?; 2016-11-02 17:11:13,554:DEBUG main (BaseJdbcLogger.java:145) - ==> Parameters: 2(Integer)2016-11-02 17:11:13,572:TRACE main (BaseJdbcLogger.java:151) - <==    Columns: id, firstName, lastName, birthDate, sex, phoneNo2016-11-02 17:11:13,573:TRACE main (BaseJdbcLogger.java:151) - <==        Row: 2, 八, 李, 2015-08-07, F, 136258963212016-11-02 17:11:13,582:DEBUG main (BaseJdbcLogger.java:145) - <==      Total: 12016-11-02 17:11:13,665:INFO main (MySpringBootApplicationTests.java:149) - 1st time: {"id":2,"firstName":"八","lastName":"李","birthDate":1438876800000,"sex":"F","phoneNo":"13625896321"}第二次：2016-11-02 17:11:13,666:INFO main (MySpringBootApplicationTests.java:153) - 2nd time: {"id":2,"firstName":"八","lastName":"李","birthDate":1438876800000,"sex":"F","phoneNo":"13625896321"}第三次：2016-11-02 17:11:18,668:DEBUG main (PersonService.java:27) - getting data from database, personId=22016-11-02 17:11:18,669:DEBUG main (BaseJdbcLogger.java:145) - ==>  Preparing: SELECT id, first_name AS firstName, last_name AS lastName, birth_date AS birthDate, sex, phone_no AS phoneNo FROM test.t_person WHERE id=?; 2016-11-02 17:11:18,670:DEBUG main (BaseJdbcLogger.java:145) - ==> Parameters: 2(Integer)2016-11-02 17:11:18,671:TRACE main (BaseJdbcLogger.java:151) - <==    Columns: id, firstName, lastName, birthDate, sex, phoneNo2016-11-02 17:11:18,672:TRACE main (BaseJdbcLogger.java:151) - <==        Row: 2, 八, 李, 2015-08-07, F, 136258963212016-11-02 17:11:18,672:DEBUG main (BaseJdbcLogger.java:145) - <==      Total: 12016-11-02 17:11:18,673:INFO main (MySpringBootApplicationTests.java:159) - 3rd time: {"id":2,"firstName":"八","lastName":"李","birthDate":1438876800000,"sex":"F","phoneNo":"13625896321"}第四次：2016-11-02 17:11:18,674:INFO main (MySpringBootApplicationTests.java:163) - 4th time: {"id":2,"firstName":"八","lastName":"李","birthDate":1438876800000,"sex":"F","phoneNo":"13625896321"}

Perfect!!!

完整的源代码：https://github.com/xujijun/my-spring-boot