[ISSUE #3215] polish litePullConsumer seek logic #3216

client/src/main/java/org/apache/rocketmq/client/impl/consumer/DefaultLitePullConsumerImpl.java

@@ -593,8 +593,19 @@ public class DefaultLitePullConsumerImpl implements MQConsumerInner {
         }
         final Object objLock = messageQueueLock.fetchLockObject(messageQueue);
         synchronized (objLock) {
-            assignedMessageQueue.setSeekOffset(messageQueue, offset);
             clearMessageQueueInCache(messageQueue);
+
+            PullTaskImpl oldPullTaskImpl = this.taskTable.get(messageQueue);
+            if (oldPullTaskImpl != null) {
+                oldPullTaskImpl.tryInterrupt();
+                this.taskTable.remove(messageQueue);
+            }
+            assignedMessageQueue.setSeekOffset(messageQueue, offset);
+            if (!this.taskTable.containsKey(messageQueue)) {
+                PullTaskImpl pullTask = new PullTaskImpl(messageQueue);
+                this.taskTable.put(messageQueue, pullTask);
+                this.scheduledThreadPoolExecutor.schedule(pullTask, 0, TimeUnit.MILLISECONDS);
+            }
         }
     }
 
@@ -718,16 +729,29 @@ public class DefaultLitePullConsumerImpl implements MQConsumerInner {
     public class PullTaskImpl implements Runnable {
         private final MessageQueue messageQueue;
         private volatile boolean cancelled = false;
+        private Thread currentThread;
 
         public PullTaskImpl(final MessageQueue messageQueue) {
             this.messageQueue = messageQueue;
         }
 
+        public void tryInterrupt() {
+            setCancelled(true);
+            if (currentThread == null) {
+                return;
+            }
+            if (!currentThread.isInterrupted()) {
+                currentThread.interrupt();
+            }
+        }
+
         @Override
         public void run() {
 
             if (!this.isCancelled()) {
 
+                this.currentThread = Thread.currentThread();
+
                 if (assignedMessageQueue.isPaused(messageQueue)) {
                     scheduledThreadPoolExecutor.schedule(this, PULL_TIME_DELAY_MILLS_WHEN_PAUSE, TimeUnit.MILLISECONDS);
                     log.debug("Message Queue: {} has been paused!", messageQueue);