【优化】 优化线程池，避免线程过多，造成卡顿

exam-module-judgement/exam-module-judgement-biz/src/main/java/pc/exam/pp/module/judgement/service/TaskManager.java

@@ -28,46 +28,38 @@ public class TaskManager {
 
     /** 开始任务（每秒执行一次） */
     public void startTask(StuInTheExam stuInTheExam, StuTheExamInfo stuTheExamInfo, String token, AtomicInteger countdown, AtomicInteger counter) {
-        // 已存在就不重复启动
+        tasks.computeIfAbsent(token, k -> {
-        tasks.computeIfAbsent(token, k ->
+            Runnable task = safe(() -> {
-                scheduler.scheduleAtFixedRate(safe(() -> {
-                    // 每秒 + 1
                 int current = counter.incrementAndGet();
-                    // 获取当前值并递减
                 int remaining = countdown.decrementAndGet();
                 log.debug("任务 {} tick at {}", token, System.currentTimeMillis());
 
                 if (current == stuInTheExam.getTimes()) {
-                        // 提示学生端进行文件的上传
                     stuTheExamInfo.setUpload(0);
-                        // 重新进行计时
                     counter.set(0);
                 }
-                    // 如果计数减到0，取消任务
                 if (remaining <= 0) {
-                        ScheduledFuture<?> future = tasks.get(token);
+                    ScheduledFuture<?> future = tasks.remove(token);
                     if (future != null) {
                         future.cancel(false);
-                            tasks.remove(token);
-                            // 发送最后一条消息
                         stuTheExamInfo.setEndStatus(0);
                         log.info("任务 {} 已完成并取消", token);
                     }
                 }
-                    // 时间转变
+                stuTheExamInfo.setTime(formatLongDuration(remaining));
-                    String time = formatLongDuration(remaining);
-                    stuTheExamInfo.setTime(time);
                 webSocketSenderApi.sendObject(UserTypeEnum.ADMIN.getValue(), "InTheExam", stuTheExamInfo);
-                }), 0, 1, TimeUnit.SECONDS)
+            });
-        );
+            return scheduler.scheduleAtFixedRate(task, 0, 1, TimeUnit.SECONDS);
+        });
         log.info("任务 {} 已启动", token);
     }
 
     /** 结束任务 */
     public void stopTask(String token) {
-        ScheduledFuture<?> f = tasks.remove(token);
+        ScheduledFuture<?> future = tasks.get(token);
-        if (f != null) {
+        if (future != null) {
-            f.cancel(false);
+            future.cancel(false);
+            tasks.remove(token);
             log.info("任务 {} 已停止", token);
         } else {
             log.warn("任务 {} 不存在", token);