How to solve the issue of Java dynamic scheduled tasks being lost after restart?

You can use frameworks like Quartz or Spring Task in Java to implement dynamic scheduled tasks. If your dynamic scheduled tasks disappear after a restart, it may be because the task configuration information was not saved correctly, causing the tasks to be re-registered.

Here is the solution:

1. Ensure that the task configuration information is correctly persisted in the database or a file. This way, the task configuration information can be read from persistent storage after a reboot and the tasks can be re-registered.
2. Before starting the task, check if it has already been registered. If it has, do not register it again to prevent duplicate tasks.
3. After initiating the task, regularly check its status. If the task status is abnormal, you can try to re-register the task.
4. In a clustered environment, make sure that task registration information is synchronized across the cluster. Using distributed locks can ensure that only one node is responsible for registering tasks.

The above are some common solutions, the specific implementation method needs to be determined based on the specific framework and requirements.