com.tencent.polaris.api.plugin.registry.CacheHandler Maven / Gradle / Ivy
/*
* Tencent is pleased to support the open source community by making Polaris available.
*
* Copyright (C) 2019 THL A29 Limited, a Tencent company. All rights reserved.
*
* Licensed under the BSD 3-Clause License (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://opensource.org/licenses/BSD-3-Clause
*
* Unless required by applicable law or agreed to in writing, software distributed
* under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
* CONDITIONS OF ANY KIND, either express or implied. See the License for the
* specific language governing permissions and limitations under the License.
*/
package com.tencent.polaris.api.plugin.registry;
import com.tencent.polaris.api.pojo.RegistryCacheValue;
import com.tencent.polaris.api.pojo.ServiceEventKey.EventType;
/**
* 缓存处理操作对象，为不同的类型的缓存提供处理能力
*/
public interface CacheHandler {
enum CachedStatus {
/**
* cache不存在
*/
CacheNotExists,
/**
* cache发生变更
*/
CacheChanged,
/**
* cache未发生变更
*/
CacheNotChanged,
/**
* cache是空的，但是server没有返回data
*/
CacheEmptyButNoData
}
/**
* 获取缓存类型
*
* @return 缓存类型
*/
EventType getTargetEventType();
/**
* 比较缓存值是否发生变更
*
* @param oldValue 旧值
* @param newValue 新值
* @return 状态
*/
CachedStatus compareMessage(RegistryCacheValue oldValue, Object newValue);
/**
* 将服务端原始消息转换为缓存对象
*
* @param oldValue 旧值
* @param newValue 新原始消息
* @param isCacheLoaded 是否从本地缓存加载
* @return 新缓存值
*/
RegistryCacheValue messageToCacheValue(RegistryCacheValue oldValue, Object newValue, boolean isCacheLoaded);
}