前言

用于分布式程序彼此之间不能同时执行的场景。例如计算程序等。

代码

锁工具类

@Component
public class RedisLockUtil {

	@Autowired
	private RedisTemplate redisTemplate;

	private static final String CALC_LOCK_KEY = "CalculateLock";
	private static final Long CALC_LOCK_TIME = 30L;


	public boolean setIfAbsent (String key,String value,Long lockTime) {
		return redisTemplate.opsForValue().setIfAbsent(key,value,lockTime,TimeUnit.MINUTES);
	}

	public String getValue(String key) {
		return (String) redisTemplate.opsForValue().get(key);
	}

	public void delete (String key) {
		redisTemplate.delete(key);
	}

	public boolean calcLock (String value) {
		return redisTemplate.opsForValue().setIfAbsent(CALC_LOCK_KEY,CALC_LOCK_TIME,TimeUnit.MINUTES);
	}

	public String getCalcValue () {
		return (String) redisTemplate.opsForValue().get(CALC_LOCK_KEY);
	}

	public String getTimeSeed(){
		return String.valueOf(new Date().getTime());
	}

	public void unCalclock () {
		redisTemplate.delete(CALC_LOCK_KEY);
	}


}

实际调用的代码

@PostMapping("/calc")
public void calc() throws Exception{

	String redisValue = "计算"+redisLockUtil.getTimeSeed();
	boolean flag = redisLockUtil.calcLock(redisValue);
	if(!flag){
		return ;
	}
	try{
		//业务代码
	}catch (Exception e){
		e.printStackTrace();
		//业务代码
		return ;
	}finally {
		//为了防止过期导致删除了其他人的锁
		if(redisValue.equals(redisLockUtil.getCalcValue())){
			redisLockUtil.unCalclock();
		}
	}
	return;
}