Hazelcast原理及使用

<dependency>
    <groupId>com.hazelcast</groupId>
    <artifactId>hazelcast-all</artifactId>
    <version>4.2.7</version>
</dependency>

package com.example.team6.util;
import com.hazelcast.core.HazelcastInstance;
import com.hazelcast.map.IMap;
import java.util.concurrent.TimeUnit;
public class HazelCastUtils {
    private final HazelcastInstance hazelcastInstance;
    private static final String MAP_NAME = "test:cache";
    public HazelCastUtils(HazelcastInstance hazelcastInstance) {
        this.hazelcastInstance = hazelcastInstance;
    }
    public Object get(String key) {
        IMap<Object, Object> map = hazelcastInstance.getMap(MAP_NAME);
        return map.get(key);
    }
    public void set(String key, String value, Integer ttl, TimeUnit timeUnit) {
        IMap<Object, Object> map = hazelcastInstance.getMap(MAP_NAME);
        map.put(key, value, ttl, timeUnit);
    }
    public void del(String key) {
        IMap<Object, Object> map = hazelcastInstance.getMap(MAP_NAME);
        map.remove(key);
    }
    public void delAllCache() {
        IMap<Object, Object> map = hazelcastInstance.getMap(MAP_NAME);
        map.clear();
    }
}

package com.example.team6.config;
import com.example.team6.util.HazelCastUtils;
import com.hazelcast.config.*;
import com.hazelcast.instance.impl.HazelcastInstanceFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
@Configuration
public class HazelcastConfiguration {
    @Bean
    @Primary
    public Config config() {
        EvictionConfig evictionConfig = new EvictionConfig();
        //数据释放策略[NONE|LRU|LFU]。这是Map作为缓存的一个参数，用于指定数据的回收算法，默认为NONE。
        //
        //NONE：当设置为NONE时，不会发生数据回收，同时max-size会失效。但是任然可以使用time-to-live-seconds和max-idle-seconds参数来控制数据留存时间。
        //
        //LRU：“最近最少使用“策略。
        //
        //LFU：“最不常用的使用”策略。
        evictionConfig.setEvictionPolicy(EvictionPolicy.LRU);
        evictionConfig.setMaxSizePolicy(MaxSizePolicy.FREE_HEAP_SIZE);
        Config config = new Config();
        config.setInstanceName("testInstanceName")
                .setClusterName("testClusterName")
                .addMapConfig(new MapConfig()
                        .setName("testName")
                        .setEvictionConfig(evictionConfig)
                        //数据留存时间[0~Integer.MAX_VALUE]。缓存相关参数，单位秒，
                        // 默认为0。这个参数决定了一条数据在map中的停留时间。
                        // 当数据在Map中留存超过这个时间并且没有被更新时，它会根据指定的回收策略从Map中移除。值为0时，意味着无求大。
                        .setTimeToLiveSeconds(10));
        return config;
    }
    @Bean
    public HazelCastUtils hazelCastUtils(Config config) {
        return new HazelCastUtils(HazelcastInstanceFactory.getOrCreateHazelcastInstance(config));
    }
}

package com.example.team6.controller;
import com.alibaba.fastjson.JSONObject;
import com.example.team6.util.HazelCastUtils;
import com.example.team6.util.UserDTO;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.concurrent.TimeUnit;
@Slf4j
@RestController
@RequestMapping("/hazelcast")
public class HazelcastController {
    @Autowired
    private HazelCastUtils hazelCastUtils;
    @PostMapping(value = "/save")
    public String saveMapData(@RequestParam String key, @RequestParam String value) {
        UserDTO userDTO=UserDTO.builder().userId(1).userName(value).build();
        hazelCastUtils.set(key, JSONObject.toJSONString(userDTO), 60, TimeUnit.SECONDS);
        return "success";
    }
    @GetMapping(value = "/get")
    public Object getMapData(@RequestParam String key) {
        return hazelCastUtils.get(key);
    }
    @GetMapping(value = "/del")
    public String del(@RequestParam String key) {
        hazelCastUtils.del(key);
        return "success";
    }
    @GetMapping(value = "/clear")
    public String clear() {
        hazelCastUtils.delAllCache();
        return "success";
    }
}