Springboot 如何使用本地緩存Caffeine

<dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-cache</artifactId>
    </dependency>
    <!-- caffeine -->
    <dependency>
      <groupId>com.github.ben-manes.caffeine</groupId>
      <artifactId>caffeine</artifactId>
      <version>2.7.0</version>
    </dependency>

//定義緩存,可直接使用
  @Bean
  public LoadingCache expiryCache(){
    LoadingCache<String, Object> loadingCache = Caffeine.newBuilder()
        .initialCapacity(100)
        .maximumSize(1000)
        //緩存寫入/刪除監(jiān)控
        .writer(new CacheWriter<Object, Object>() {
          @Override
          public void write(Object key, Object value) { //此方法是同步阻塞的
            System.out.println("--緩存寫入--:key=" + key + ", value=" + value);
          }
          @Override
          public void delete(Object key, Object value, RemovalCause cause) { System.out.println("--緩存刪除--:key=" + key); }
        })
        .expireAfterAccess(1, TimeUnit.MINUTES) //過期時間
        .build((String key)->"刷新的數(shù)據(jù)"); //cacheload實現(xiàn)類,刷新時候調(diào)用
    loadingCache.put("name","侯征");
    return loadingCache;
  }

@Autowired
  private LoadingCache loadingCache;
  @GetMapping("/get")
  public Object getValue(String key){
    return loadingCache.get(key);
  }
  @GetMapping("/add")
  public void addValue(String value){
    loadingCache.put(value,value);
  }
  @GetMapping("/delete")
  public void deleteValue(String key){
    loadingCache.invalidate(key);
    loadingCache.invalidateAll();//清楚所有
  }
  @GetMapping("/refresh")
  public void refreshValue(String key){
    //刷新時會根據(jù)build方法中中指定的cacheload重新加載
    loadingCache.refresh(key);
  }

//配置CacheManager
  @Bean(name = "caffeine")
  public CacheManager cacheManagerWithCaffeine() {
    CaffeineCacheManager cacheManager = new CaffeineCacheManager();
    Caffeine caffeine = Caffeine.newBuilder()
        //cache的初始容量值
        .initialCapacity(100)
        //maximumSize用來控制cache的最大緩存數(shù)量，maximumSize和maximumWeight(最大權(quán)重)不可以同時使用，
        .maximumSize(1000)
        //最后一次寫入或者訪問后過久過期
        .expireAfterAccess(500, TimeUnit.SECONDS)
        //創(chuàng)建或更新之后多久刷新,需要設置cacheLoader
        .refreshAfterWrite(10, TimeUnit.SECONDS);
    cacheManager.setCaffeine(caffeine);
    cacheManager.setCacheLoader(cacheLoader);
    cacheManager.setCacheNames(names);//根據(jù)名字可以創(chuàng)建多個cache，但是多個cache使用相同的策略
    cacheManager.setAllowNullValues(false);//是否允許值為空
    return cacheManager;
  }

/**
   * 必須要指定這個Bean，refreshAfterWrite配置屬性才生效
   */
  @Bean
  public CacheLoader<Object, Object> cacheLoader() {
    return new CacheLoader<Object, Object>() {
      @Override
      public Object load(Object key) throws Exception { return null;}
      // 重寫這個方法將oldValue值返回回去，進而刷新緩存
      @Override
      public Object reload(Object key, Object oldValue) throws Exception {
        System.out.println("--refresh--:"+key);
        return oldValue;
      }
    };
  }