异步任务问题

• 資深大佬 : dqzcwxb

  加个锁

• 資深大佬 : stonewu

  最简单的方式就是定义一个全局变量

• 主 資深大佬 : qm332207252

  @dqzcwxb 能详细点说明下不

• 資深大佬 : zoharSoul

  记到任务表.

• 主 資深大佬 : qm332207252

  @stonewu 我也想过在调用异步方法外面用个什么变量标记执行状态

• 資深大佬 : MicroGalaxy

  这种需求还是全局变量最简单好用

• 主 資深大佬 : qm332207252

  @MicroGalaxy 类似前端做登录按钮,请求表格数据什么的异步请求加状态标记那样咯?

• 資深大佬 : killergun

  Ticket ？根据 Ticket 来获取进展

• 資深大佬 : guoyuchuan

  异步任务可以配置线程池，这样就不会存在你说的这个问题了

• 資深大佬 : guoyuchuan

  @guoyuchuan #9 不对，说错了

• 資深大佬 : liian2019

  单机就整个 AtomicBoolean，分布式就整个 redis 记一下

• 資深大佬 : RedBeanIce

  java 异步任务有很多方法，CompletableFuture.runAsync

  至于第二次进来的问题，加个锁就行，上有说明，单机和分布式

• 資深大佬 : oneisall8955

  单机还是集群，单机配只静态变量，集群搞 redis，加个 key 标识

• 資深大佬 : siweipancc

  占坑#

• 資深大佬 : siweipancc

  @Log
  @RestController
  @SpringBootApplication
  public class WebApplication {

  public static void main(String[] args) {
  SpringApplication.run(WebApplication.class, args);
  }

  static final String CREATED = “create”;
  static final String PROCESS = “process”;
  static final String COMPLETE = “complete”;

  @PostMapping(“generate”)
  public ResponseEntity<Response> generate(@RequestBody Request request) {
  return ResponseEntity.ok(generate(request.input, request.taskId));
  }

  @Autowired
  private RedisTemplate<Object, Object> redisTemplate;
  @Autowired
  private ThreadPoolTaskExecutor executor;

  @PostConstruct
  public void init() {
  redisTemplate.setKeySerializer(RedisSerializer.string());
  redisTemplate.setValueSerializer(new GenericJackson2JsonRedisSerializer());
  }

  Function<UUID, String> valKeyFunc = uuid -> “value::” + uuid;
  Duration expire = Duration.ofMinutes(30L);

  public Response generate(Integer input, UUID taskId) {

  if (taskId == null) {
  check(input != null, “请输入值”);
  UUID uuid = createTask(input);
  return new Response(CREATED, null, uuid, expire.getSeconds());
  }

  String key = valKeyFunc.apply(taskId);
  Long expire = redisTemplate.getExpire(key);
  Entity value;
  try {
  value = (Entity) redisTemplate.opsForValue().get(key);
  } catch (ClassCastException e) {
  log.warning(e.getMessage());
  e.printStackTrace();
  throw new RuntimeException(“服务器内部错误”);
  }
  check(value != null, “任务 ” + taskId + ” 不存在或者已经过期”);
  assert value != null;
  check(value.complete != null, “服务器内部错误”);
  if (!value.complete) {
  return new Response(PROCESS, null, taskId, expire);
  }

  return new Response(COMPLETE, value, taskId, expire);
  }

  private static void check(Boolean condition, String msg) {
  if (!Boolean.TRUE.equals(condition)) {
  throw new RuntimeException(msg);
  }
  }

  private UUID createTask(Integer input) {
  UUID uuid = UUID.randomUUID();
  executor.execute(() -> {
  try {
  Entity entity = new Entity(uuid, false, new Date(), null, input, null);
  log.info(String.format(“begin task: %s, input: %s”, uuid, input));
  String key = valKeyFunc.apply(uuid);
  redisTemplate.opsForValue().set(key, entity, expire);
  log.info(String.format(“set task: %s, input: %s, key: %s”, uuid, input, key));
  TimeUnit.SECONDS.sleep(RandomUtil.randomInt(10, 20));
  String value = RandomUtil.randomString(Math.abs(input));
  entity.complete = true;
  entity.completeTime = new Date();
  entity.output = value;
  log.info(String.format(“end task: %s, input: %s, generated: %s”, uuid, input, value));
  redisTemplate.opsForValue().set(key, entity, expire);
  } catch (InterruptedException e) {
  log.warning(e.getMessage());
  e.printStackTrace();
  }
  });
  return uuid;
  }

  @Data
  static class Request {
  Integer input;
  UUID taskId;
  }

  @AllArgsConstructor
  @NoArgsConstructor
  @Data
  static class Response {
  String status;
  Object data;
  UUID taskId;
  Long expire;
  }

  @Data
  @AllArgsConstructor
  @NoArgsConstructor
  static class Entity {
  UUID taskId;
  Boolean complete;
  Date beginTime;
  Date completeTime;

  Integer input;
  String output;
  }

  }