What is the meaning of following error? How I can recover it?
Exception in thread "UserActionProcessor-8811" java.util.concurrent.RejectedExecutionException: Task java.util.concurrent.FutureTask@56624074 rejected from java.util.concurrent.ThreadPoolExecutor@5fd03556[Running, pool size = 300, active threads = 300, queued tasks = 2000, completed tasks = 7979]
at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:2048)
at java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:821)
at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1372)
at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:110)