介绍redis分布式锁-Redis

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Redisson

redisson和下列一下自行封装两种方式的区别（场景）：

1. redisson未获取到锁的会进入等待，直到获取到锁。
2. 另外两种方式如果未获取到锁，会放弃，不会执行业务代码。

<dependency>    <groupId>org.redisson</groupId>    <artifactId>redisson-spring-boot-starter</artifactId>    <version>3.13.6</version></dependency>

@Autowiredprivate Redisson redisson;@GetMapping("/redissonLock")public String redissonLock() {    log.info("进入了方法");    RLock lock = redisson.getLock("redissonLock");    try {        lock.lock(30, TimeUnit.SECONDS);        Thread.sleep(10000);        System.out.println("我是你大哥");    } catch (InterruptedException e) {        e.printStackTrace();    } finally {    // 如果不释放，不会唤起其他线程，则其他线程会超时过期自动唤醒，不会执行业务代码        lock.unlock();    }    return "运行结束";}

RedisTemplate封装redis锁（1）

<dependency>   <groupId>org.springframework.boot</groupId>   <artifactId>spring-boot-starter-data-redis</artifactId></dependency>

package com.util;import org.springframework.dao.DataAccessException;import org.springframework.data.redis.connection.RedisConnection;import org.springframework.data.redis.connection.RedisStringCommands;import org.springframework.data.redis.core.RedisCallback;import org.springframework.data.redis.core.RedisTemplate;import org.springframework.data.redis.core.script.RedisScript;import org.springframework.data.redis.core.types.Expiration;import org.springframework.stereotype.Component;import java.util.Arrays;@Componentpublic class RedisLock {    private static RedisTemplate redisTemplate;    private static String script = "if redis.call(\"get\",KEYS[1]) == ARGV[1] then\n" +            "\treturn redis.call(\"del\",KEYS[1])\n" +            "else\n" +            "   \treturn 0\t\n" +            "end  ";    public RedisLock(RedisTemplate redisTemplate) {        RedisLock.redisTemplate = redisTemplate;    }    public static Boolean getLock(String key, String value, Long expireTime) {        RedisStringCommands.SetOption setOption = RedisStringCommands.SetOption.ifAbsent();        Expiration expiration = Expiration.seconds(expireTime);        RedisCallback<Boolean> booleanRedisCallback = new RedisCallback<Boolean>() {            @Override            public Boolean doInRedis(RedisConnection connection) throws DataAccessException {                return connection.set(redisTemplate.getKeySerializer().serialize(key), redisTemplate.getValueSerializer().serialize(value), expiration, setOption);            }        };        return (Boolean) redisTemplate.execute(booleanRedisCallback);    }    public static Boolean unLock(String key, String value) {        RedisScript<Boolean> redisScript = RedisScript.of(script, Boolean.class);        return (Boolean) redisTemplate.execute(redisScript, Arrays.asList(key), value);    }}

@GetMapping("/redisLock")public String redisLock() {    log.info("进入了方法");    String key = "redisLock";    String uuid = UUID.randomUUID().toString();    try {        if (RedisLock.getLock(key, uuid, 30L)) {            log.info("进入了锁");            Thread.sleep(10000);        }    } catch (InterruptedException e) {        e.printStackTrace();    } finally {        RedisLock.unLock(key, uuid);    }    log.info("方法执行完成");    return "程序结束";}

RedisTemplate封装redis锁（2）

package com.util;import lombok.extern.slf4j.Slf4j;import org.springframework.dao.DataAccessException;import org.springframework.data.redis.connection.RedisConnection;import org.springframework.data.redis.connection.RedisStringCommands;import org.springframework.data.redis.core.RedisCallback;import org.springframework.data.redis.core.RedisTemplate;import org.springframework.data.redis.core.script.RedisScript;import org.springframework.data.redis.core.types.Expiration;import java.util.Arrays;import java.util.UUID;@Slf4jpublic class HighRedisLock implements AutoCloseable{    private RedisTemplate redisTemplate;    private String key;    private String value;    private Long expireTime;    private static String script = "if redis.call(\"get\",KEYS[1]) == ARGV[1] then\n" +            "\treturn redis.call(\"del\",KEYS[1])\n" +            "else\n" +            "   \treturn 0\t\n" +            "end  ";    public HighRedisLock(RedisTemplate redisTemplate, String key, Long expireTime) {        this.redisTemplate = redisTemplate;        this.key = key;        this.value = UUID.randomUUID().toString();        this.expireTime = expireTime;    }    public Boolean getLock() {        RedisStringCommands.SetOption setOption = RedisStringCommands.SetOption.ifAbsent();        Expiration expiration = Expiration.seconds(expireTime);        RedisCallback<Boolean> booleanRedisCallback = new RedisCallback<Boolean>() {            @Override            public Boolean doInRedis(RedisConnection connection) throws DataAccessException {                return connection.set(redisTemplate.getKeySerializer().serialize(key), redisTemplate.getValueSerializer().serialize(value), expiration, setOption);            }        };        return (Boolean) redisTemplate.execute(booleanRedisCallback);    }    public Boolean unLock() {        RedisScript<Boolean> redisScript = RedisScript.of(script, Boolean.class);        return (Boolean) redisTemplate.execute(redisScript, Arrays.asList(key), value);    }    @Override    public void close() throws Exception {        unLock();    }}

@Autowiredprivate RedisTemplate redisTemplate;@GetMapping("/highRedisLock")public String highRedisLock() {    log.info("进入了方法");    try (HighRedisLock redisLock = new HighRedisLock(redisTemplate, "highRedisLock", 30L)) {        if (redisLock.getLock()) {            log.info("进入了锁");            Thread.sleep(10000);        }    } catch (InterruptedException e) {        e.printStackTrace();    } catch (Exception e) {        e.printStackTrace();    }    log.info("方法执行完成");    return "程序结束";}

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