JetCache系列 -- Cache 的使用场景和其详细使用

pom:

    <dependency>
            <groupId>com.weishi</groupId>
            <artifactId>jetcache-starter-redis-lettuce</artifactId>
            <exclusions>
                <exclusion>
                    <artifactId>minlog</artifactId>
                    <groupId>com.esotericsoftware</groupId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>com.weishi</groupId>
            <artifactId>jetcache-anno-api</artifactId>
        </dependency>

        <dependency>
            <groupId>com.weishi</groupId>
            <artifactId>jetcache-core</artifactId>
        </dependency>





App class:

@SpringBootApplication
@EnableMethodCache(basePackages = "com.company.mypackage")
@EnableCreateCacheAnnotation
public class MySpringBootApp {
    public static void main(String[] args) {
        SpringApplication.run(MySpringBootApp.class);
    }
}

jetcache:
  statIntervalMinutes: 15                 //统一间隔
  areaInCacheName: false                  //设置不把areaName作为Key前缀
  hiddenPackages: com.alibaba   //如果@Cached和@CreateCache的name是自动生成的，会默认的将包 名和方法名作为前缀，为了不让name太长，该设置时将制定的包名截掉
                         
  local:
    default:
      type: caffeine                //缓存类型,caffeine 
      limit: 100                    //
      keyConvertor: fastjson        //Key转换器的全局变量
      expireAfterWriteInMillis: 100000 // ms, 写入多久后 会被清理掉
    otherArea:
      type: linkedhashmap   // lru 算法
      limit: 100
      keyConvertor: none
      expireAfterWriteInMillis: 100000
  remote:
    default:
      type: redis  # 同步的redis 客户端， redis.lettuce 异步的redis 客户端
      keyPrefix: jedisTest_A1  // prefix 设置
      keyConvertor: fastjson
      valueEncoder: java
      valueDecoder: java
      poolConfig:
        minIdle: 5
        maxIdle: 20
        maxTotal: 50  
      host: ${redis.host}
      port: ${redis.port}
    otherArea:
      type: redis.lettuce
      keyConvertor: fastjson
      valueEncoder: kryo
      valueDecoder: kryo
      poolConfig:
        minIdle: 5
        maxIdle: 20
        maxTotal: 50
     uri: redis://127.0.0.1:6379/   # sentinels 的方式(uri: redis-sentinel://127.0.0.1:26379,127.0.0.1:26380,127.0.0.1:26381/?sentinelMasterId=mymaster)
	 keyPrefix: lettuceClusterTest3  
	 

    
     

key转换器的全局配置，当前只有一个已经实现的keyConvertor：fastjson。仅当使用@CreateCache且缓存类型为LOCAL是可以指定为none，此时通过equals方法来识别key。方法缓存必须指定keyConvertor

jetcache.local.${area}.expireAfterAccessInMillis

 @CreateCache(name = "ws_user", expire = 3, timeUnit = TimeUnit.MINUTES,
            localExpire = 2, cacheType = CacheType.BOTH, localLimit = 2000, serialPolicy = SerialPolicy.JAVA,
            keyConvertor = KeyConvertor.FASTJSON)
 Cache<Serializable, UserEntity> multiLevelCache;


 @CreateCache(name ="ws_gift",cacheType = CacheType.BOTH)
 Cache<Serializable,GiftEntity> giftEntityCache;


@PostConstruct
public void init(){
// 手动设置 xxx
    orderSumCache.config().setXXX();

}

CacheGetResult r = cache.GET(userId);
CompletionStage<ResultData> future = r.future();
future.thenRun(() -> {
    if(r.isSuccess()){
        System.out.println(r.getValue());
    }
});

// 直接返回结果， 注意 lettuce 客户端的话，（内部实现其实是异步调用，也有其默认超时时间 1s）也需要注意判空
V value=cache.getValue(userId);

cache.PUT(userId);

cache.REMOVE(userId);

//还有一些大写开头的方法，都是可以异步调用

CacheGetResult<OrderDO> r = cache.GET(orderId);
if( r.isSuccess() ){
    OrderDO order = r.getValue();
} else if (r.getResultCode() == CacheResultCode.NOT_EXISTS) {
    System.out.println("cache miss:" + orderId);
} else if(r.getResultCode() == CacheResultCode.EXPIRED) {
    System.out.println("cache expired:" + orderId));
} else {
    System.out.println("cache get error:" + orderId);
}

public interface UserService {
    @Cached(name="userCache-", key="#userId", expire = 3600)
    @CachePenetrationProtect
    User getUserById(long userId);

	@CacheInvalidate(name="userCache-", key="#user.userId")
    void updateUser(User user);

    @CacheInvalidate(name="userCache-", key="#userId")
    void deleteUser(long userId);
}

public interface SummaryService{
    @Cached(expire = 3600, cacheType = CacheType.REMOTE)
    @CacheRefresh(refresh = 1800, stopRefreshAfterLastAccess = 3600, timeUnit = TimeUnit.SECONDS)
    @CachePenetrationProtect
    BigDecimal summaryOfToday(long catagoryId);
}

 // 使用try-with-resource方式，可以自动释放锁
  try(AutoReleaseLock lock = cache.tryLock("MyKey",100, TimeUnit.SECONDS)){
     if(lock != null){
        // do something
     }
  }finally{
   lock.close();
}



  boolean hasRun = cache.tryLockAndRun("MyKey",100, TimeUnit.SECONDS, () -> {
    // do something
  });