高性能内存缓存框架Caffeine，Java

代码：

package org.example;

import com.github.benmanes.caffeine.cache.*;
import org.checkerframework.checker.nullness.qual.Nullable;

import java.util.concurrent.TimeUnit;

public class App {
    public static void main(String[] args) {
        try {
            new App().test();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private void test() {
        LoadingCache<String, Object> cache = Caffeine.newBuilder()
                .maximumSize(99999) //缓存中存储的最大缓存数量，如果超出就开始根据一定策略删缓存

                //在写入一定时间后删掉缓存
                .expireAfterWrite(100, TimeUnit.SECONDS)

                //在访问（get）一定时间后删掉缓存
                .expireAfterAccess(15, TimeUnit.SECONDS)

                //在一定时间后刷新缓存
                .refreshAfterWrite(30, TimeUnit.SECONDS)

                //也可自定义缓存失效策略
                /**.expireAfter(new Expiry<Object, Object>() {
                @Override public long expireAfterCreate(Object o, Object o2, long l) {
                return 0;
                }

                @Override public long expireAfterUpdate(Object o, Object o2, long l, @NonNegative long l1) {
                return 0;
                }

                @Override public long expireAfterRead(Object o, Object o2, long l, @NonNegative long l1) {
                return 0;
                }
                })
                 */

                //删除缓存监听事件
                .removalListener(new RemovalListener<Object, Object>() {
                    @Override
                    public void onRemoval(@Nullable Object o, @Nullable Object o2, RemovalCause removalCause) {
                        System.out.println(o + " remove  reason ==> " + removalCause);
                    }
                })
                .build(new CacheLoader<String, Object>() {
                    @Override
                    public @Nullable Object load(String s) throws Exception {
                        return "new data load";
                    }
                });

        String NAME = "name";
        cache.put(NAME, "zhangphil");

        //获取缓存值，如果为空，返回null
        System.out.println(cache.getIfPresent(NAME).toString());

        //使NAME这一条缓存失效。
        cache.invalidate(NAME);
        //cache.invalidateAll(); //使所有缓存失效。
        System.out.println(cache.getIfPresent(NAME) + "");

        try {
            Thread.sleep(10);
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        }
    }
}

输出：

zhangphil
null
name remove  reason ==> EXPLICIT