Java RejectedExecutionException: ThreadPoolExecutor Terminated

This exception is thrown when a task submitted to a ThreadPoolExecutor is rejected because the executor has been terminated. In other words, the executor is no longer accepting new tasks because it has already been shut down.

Possible causes of this exception can include:

1. Attempting to submit a task to a ThreadPoolExecutor that has already been shut down.
2. The maximum number of threads or queue size has been reached, and the task cannot be queued or executed.
3. The task implementation itself may be causing an exception that is getting wrapped in a RejectedExecutionException.

To fix this issue, you should ensure that you are not attempting to submit tasks to an executor that has already been shut down. You may also need to adjust the maximum number of threads or queue size if you are consistently hitting capacity. Additionally, you should check the task implementation to ensure that it is not causing any unexpected exceptions.