Caffeine高性能的 Java 缓存库-初识（一）

介绍暂时不写，先粘贴一个常用用法。

public class GeneralUserCache {

    private Cache<Long, GeneralUser> userCache = Caffeine.newBuilder().maximumSize(1000).expireAfterWrite(3, TimeUnit.DAYS).build();
    public GeneralUser getUser(Long id){
        if(id == null){
            return null;
        }
        GeneralUser user = userCache.get(id, new Function<Long, GeneralUser>() {
            @Override
            public GeneralUser apply(Long aLong) {
                GeneralUser user = new GeneralUser();
                user.setId(id);
                user.setName(getUserName(id));
                return user;
            }
        });
        return user;
    }
}