Caffenie

Caffenie

性能超过redis！

Caffeine本地缓存-CSDN博客

java缓存框架Caffeine详解_java caffeine-CSDN博客

使用场景：

1、保存固定不变且经常需要用到的参数

2、读多写少的场景

使用方法

引入依赖

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<dependency>
            <groupId>com.github.ben-manes.caffeine</groupId>
            <artifactId>caffeine</artifactId>
        </dependency>

开启caffeine并且定义缓存

当然也可以设置过期时间，在读多写少的场景下也能保证数据的可靠性

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.expireAfterWrite(5,TimeUnit.MINUTES)
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@Configuration
@EnableCaching
public class CaffeineConfig {
    @Bean
    public CaffeineCacheManager caffeineCacheManager(){
        CaffeineCacheManager caffeine = new CaffeineCacheManager();
        caffeine.registerCustomCache("productDetails", Caffeine.newBuilder().recordStats().maximumSize(1000).build());
        return caffeine;
    }
}

使用缓存

他会以参数为key，保证不同参数访问的各自的数据

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@GetMapping("detail")
   @Cacheable("productDetails")
   public Result detail(@RequestParam Integer id){
       Products product = productsService.getById(id);
       sleep(1000);
       return Result.ok(product);
   }

手动加载缓存

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@Bean
   public Cache<String, Integer> caffeine() {
       Cache<String, Integer> cache = Caffeine.newBuilder()
               .expireAfterWrite(1, TimeUnit.MINUTES)
               .maximumSize(100)
               .build();
       return cache;
   }

自动加载缓存

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@Bean
    public LoadingCache<Long, User> caffeine() {
        LoadingCache<Long, User> cache = Caffeine.newBuilder()
                .maximumSize(10000)
                .expireAfterWrite(10, TimeUnit.MINUTES)
                .build(this::loadUser);
        return cache;
    }
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@Autowired
    LoadingCache<Long,User> userCache;

@GetMapping("/{id}")
    public Result getUser(@PathVariable Long id){
        User user = userCache.get(id);
        return Result.ok(user);
    }

实现接口幂等性

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@Configuration
@EnableCaching
public class CaffeineConfig {
    @Bean
    public Cache<String, Integer> caffeine() {
        Cache<String, Integer> cache = Caffeine.newBuilder()
                .expireAfterWrite(10, TimeUnit.SECONDS)
                .maximumSize(1000)
                .build();
        return cache;
    }
}

@Component
public class CaffeineUtils {
    @Autowired
    Cache<String, Integer> cache;

    public static String LOGIN_PREFIX = "login:";

    public boolean verifyIdempotent(String key) {
        //不存在将会返回null
        Integer value = cache.getIfPresent(key);
        if (value == null) {
            cache.put(key, 1);
            return false;
        }
        return true;
    }
}

//caffeine实现接口幂等性
        boolean isPresent = caffeineUtils.verifyIdempotent(CaffeineUtils.LOGIN_PREFIX + username);
        if (isPresent) {
            return new AjaxResult(AjaxResult.Type.WARN, "请勿重复提交");
        }