聊聊使用RedisTemplat实现简单的分布式锁的问题

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

@Configuration
public class RedisConfig {
    @Bean
    public RedisTemplate<String , Object> redisTemplate(RedisConnectionFactory redisConnectionFactory){
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
        //String类型 key序列器
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        //String类型 value序列器
        redisTemplate.setValueSerializer(new GenericJackson2JsonRedisSerializer());
        //Hash类型 key序列器
        redisTemplate.setHashKeySerializer(new StringRedisSerializer());
        //Hash类型 value序列器
        redisTemplate.setHashValueSerializer(new GenericJackson2JsonRedisSerializer());
        //将连接工厂注入
        redisTemplate.setConnectionFactory(redisConnectionFactory);
        return redisTemplate;
    }
 }

@SpringBootTest
class ApplicationTests {
    @Autowired
    private RedisTemplate redisTemplate;
	@Test
	public void lodsTest01(){
		ValueOperations valueOperations = redisTemplate.opsForValue();
	        //创建一个占位符，如果key不存在才可以设置成功
	        Boolean isLock = valueOperations.setIfAbsent("k1", "v1");
	        //如果占位成功，进行正常操作
	        if (isLock){
	        	//设置一个name存到redis
	            valueOperations.set("name","xxxx");
	            //从redis取出name
	            String name = (String) valueOperations.get("name");
	            System.out.println("name = " + name);
	            //手动制造异常
	            Integer.parseInt("xxxx");
	            //操作结束删除锁
	            redisTemplate.delete("k1");
	        }else{
	            System.out.println("有线程在用，请稍后在试");
	        }
	}
}

	@Test
    public void testLock02()  {
        ValueOperations valueOperations = redisTemplate.opsForValue();
        //如果key不存在才可以设置成功,设置一个有效时间防止线程异常出现死锁
        Boolean isLock = valueOperations.setIfAbsent("k1", "v1",5, TimeUnit.SECONDS);
        //如果占位成功，进行正常操作
        if (isLock){
        	//设置一个name存到redis
            valueOperations.set("name","xxxx");
            //从redis取出name
            String str = (String) valueOperations.get("name");
            System.out.println("name = " + str);
            //制造异常
            Integer.parseInt("xxxx");
            //操作结束删除锁
            redisTemplate.delete("k1");
        }else{
            System.out.println("有线程在用，请稍后在试");
        }
    }

if redis.call("get",KEYS[1])==ARGV[1] then
    return redis.call("del",KEYS[1])
else
    return 0
end

	@Bean
    public DefaultRedisScript<Boolean> defaultRedisScript(){
        DefaultRedisScript<Boolean> redisScript = new DefaultRedisScript<>();
        //lock.lua脚本位置和application.yml同级目录
        redisScript.setLocation(new ClassPathResource("lock.lua"));
        //设置类型为boolean
        redisScript.setResultType(Boolean.class);
        return redisScript;
    }

@Test
    public void testLock03(){
        ValueOperations valueOperations = redisTemplate.opsForValue();
        String value = UUID.randomUUID().toString();
        //如果key不存在才可以设置成功,设置一个value为随机数的值，防止出现线程太多 导致线程不安全
        Boolean isLock = valueOperations.setIfAbsent("k1", value, 5, TimeUnit.SECONDS);
        //如果占位成功，进行正常操作 
        if (isLock){
        	//设置一个name存到redis
            valueOperations.set("name","xxxx");
            //从redis取出name
            String name = (String) valueOperations.get("name");
            System.out.println("name = " + name);
            //为redis发送lua脚本删除锁对应的value
            Boolean aBoolean = (Boolean) redisTemplate.execute(redisScript, Collections.singletonList("k1"), value);
            System.out.println(aBoolean);
        }else{
            System.out.println("有线程在用，请稍后在试");
        }
    }