使用shedlock实现分布式互斥执行

前言

前序章节：springboot基础(82):分布式定时任务解决方案shedlock

如果你不清楚shedlock，建议先阅读前序章节，再来查看本文。

如果我们不在spring环境下，如何使用shedlock实现分布式互斥执行？

我们可以使用shedlock为我们提供的DefaultLockingTaskExecutor来实现手动调用。

示例

void executeWithLock(@NonNull Runnable var1, @NonNull LockConfiguration var2)

java 复制代码

  @GetMapping("/testRunnable")
    public R testRunnable(HttpServletRequest request) {
        log.info("进入方法");
        String name = request.getParameter("name");
        LockingTaskExecutor executor = new DefaultLockingTaskExecutor(lockProvider);
        Instant now = Instant.now();
        try {
            executor.executeWithLock(new Runnable() {
                @Override
                public void run() {
                    log.info("执行");
                    helloService.helloCn(name);
                }
            }, new LockConfiguration(now, "testRunnable", Duration.ofSeconds(30), Duration.ofSeconds(5)));
            log.info("end");
            return R.ok("success", null);
        } catch (Throwable throwable) {
            throwable.printStackTrace();
        }
        return R.fail("fail");
    }

LockingTaskExecutor.TaskResult executeWithLock(@NonNull LockingTaskExecutor.TaskWithResult task, @NonNull LockConfiguration lockConfig)

利用此API，我们可以让一个方法不能在一个时间只能有一次实例在执行，排斥调用者，且其它调用者的调用失败，这是与分布式锁不一样的地方。

java 复制代码

 @GetMapping("/testTaskWithResult")
    public R testTaskWithResult(HttpServletRequest request) {
        log.info("进入方法");
        String name = request.getParameter("name");
        LockingTaskExecutor executor = new DefaultLockingTaskExecutor(lockProvider);
        Instant now = Instant.now();
        try {
            LockingTaskExecutor.TaskResult taskResult = executor.executeWithLock(new LockingTaskExecutor.TaskWithResult() {
                @Override
                public Object call() throws Throwable {
                    log.info("执行");
                    return helloService.helloCn(name);
                }
            }, new LockConfiguration(now, "testTaskWithResult", Duration.ofSeconds(30), Duration.ofSeconds(5)));
            boolean flag = taskResult.wasExecuted();
            log.info("end");
            return R.ok("任务是否被执行:" + flag, taskResult.getResult());
        } catch (Throwable throwable) {
            throwable.printStackTrace();
        }
        return R.fail("fail");
    }

传送门

https://github.com/lukas-krecan/ShedLock