【Redisson】一.Redisson的分布式鎖-配置

前言

　　本篇主要介紹Redisson分布式鎖的配置，項目結構Springboot

 

Maven配置

        <!-- redis -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>io.lettuce</groupId>
                    <artifactId>lettuce-core</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <!-- 備注：spring-boot-data-redis默認使用luttuce連接池--->
        <!-- 備注：這里將luttuce連接池替換為jedis連接池--->
        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
        </dependency>

　　　　 <dependency>
  　　　　  <groupId>org.redisson</groupId>
  　　　　  <artifactId>redisson</artifactId>
   　　　　 <version>3.12.5</version>
　　　　 </dependency>

yml文件配置

　　注意：這里介紹單節點方式和集群方式的兩種配置

//單節點配置
  redis:
    host: x.x.x.x
    port: 6379
    password: xxxx
    database: 1
    timeout: 1000ms
    jedis:
      pool:
        max-active: 10
        max-wait: -1ms
        max-idle: 8
        min-idle: 0

//集群節點配置(cluster模式) 三主三從
  redis:
    database: 1
    timeout: 1000ms
    jedis:
      pool:
        max-active: 8
        max-wait: -1ms
        max-idle: 8
        min-idle: 0
    cluster:
      nodes:
        - a.a.a.a:port1
        - b.b.b.b:port2
        - c.c.c.c:port3
        - d.d.d.d:port4
        - e.e.e.e:port5
        - f.f.f.f:port6

配置類

package com.nn.status.config;

import lombok.extern.slf4j.Slf4j;
import org.redisson.Redisson;
import org.redisson.api.RedissonClient;
import org.redisson.config.ClusterServersConfig;
import org.redisson.config.Config;
import org.redisson.config.SingleServerConfig;
import org.springframework.boot.autoconfigure.data.redis.RedisProperties;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.util.StringUtils;

import java.util.List;
import java.util.stream.Collectors;

/**
 * @author Sam.yang
 * @since 2021/7/23 09:46
 */
@Slf4j
@Configuration
@EnableConfigurationProperties(RedisProperties.class)
public class RedissonConfiguration {
    /**
     * 初始化RedissonClient客戶端
     * 注意：
     * 此實例集群為3節點，各節點1主1從
     * 集群模式,集群節點的地址須使用“redis://”前綴，否則將會報錯。
     *
     * @param redisProperties {@link RedisProperties}
     * @return {@link RedissonClient}
     */
    @Bean
    public RedissonClient getRedissonClient(RedisProperties redisProperties) {
        Config config = new Config();
        if (redisProperties.getCluster() != null) {
            //集群模式配置
            List<String> nodes = redisProperties.getCluster().getNodes();
            nodes = nodes.stream().map(node -> "redis://" + node).collect(Collectors.toList());
            ClusterServersConfig clusterServersConfig = config.useClusterServers();
            clusterServersConfig.addNodeAddress(nodes.toArray(new String[nodes.size()]));
            if (!StringUtils.isEmpty(redisProperties.getPassword())) {
                clusterServersConfig.setPassword(redisProperties.getPassword());
            }
        } else {
            //單節點配置
            String address = "redis://" + redisProperties.getHost() + ":" + redisProperties.getPort();
            SingleServerConfig serverConfig = config.useSingleServer();
            serverConfig.setAddress(address);
            if (!StringUtils.isEmpty(redisProperties.getPassword())) {
                serverConfig.setPassword(redisProperties.getPassword());
            }
            serverConfig.setDatabase(redisProperties.getDatabase());
        }
        //看門狗的鎖續期時間，默認30000ms，這里配置成15000ms
        config.setLockWatchdogTimeout(15000);
        return Redisson.create(config);
    }
}

DEMO

        //拿鎖失敗時會不停的重試
        RLock lock = redissonClient.getLock("serviceKey");
        lock.lock(); //具有Watch Dog自動延期機制 默認續30s 每隔30/3=10 秒續到30s

        boolean res1 = lock.tryLock(10, TimeUnit.SECONDS);
        //返回false:表示嘗試拿鎖10s，仍然沒有獲取到鎖，停止重試
        //返回true: 表示已經獲取到鎖，默認具備WatchDog自動延期機制，續30s

        lock.lock(10, TimeUnit.SECONDS); //指定了釋放時間，WatchDog不生效,10s后自動釋放，
       
        boolean res2 = lock.tryLock(100, 10, TimeUnit.SECONDS);
        //嘗試拿鎖100s后停止重試,返回false,指定WatchDog,10s后自動釋放
        Thread.sleep(40000L);
        lock.unlock();