Issue with Java Shutdown hook

Question

My test code is like following :

public static void main(String[] args) throws IOException, InterruptedException {
        // TODO Auto-generated method stub

        while(true) {
            Runtime.getRuntime().addShutdownHook(new Thread(new Runnable() 
            { 
              public void run() 
              { 
                System.out.println("Shutdown Hook is running !"); 
                System.out.println("Application Terminating ...");
              } 
            })); 
            System.out.println("Running");
        } 
    }

I run the code in eclipse, go to debug tab where I can see it in running state.I do right click -> terminate .And shutdown hook won't execute.

Output printed :

Running
Running
Running
.
.
.
.
.
.

Duplicate of [How to gracefully handle the SIGKILL signal in Java](https://stackoverflow.com/questions/2541597/how-to-gracefully-handle-the-sigkill-signal-in-java) — searchengine27, Jun 10 '20 at 13:43

score 4 · Accepted Answer · answered Jun 10 '20 at 13:43

4

You can't handle that case. It seems Eclipse is sending a SIGKILL which is not part of a graceful shutdown, and thereby cannot be caught. See https://stackoverflow.com/a/2541618/3560873

answered Jun 10 '20 at 13:43

searchengine27

1,449
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26

score 0 · Answer 2 · answered Jun 10 '20 at 13:49

.. and eclipse is unlikely to grow the ability to send the nice 'please terminate' signal (which is called SIGTERM, which causes shutdown hooks to run), because java's Process API only has one method to exit the process, and this is implemented with sending SIGKILL.

If you want to test your shutdown hooks, just.. invoke System.exit(0) within your own app, and you'll witness your shutdown hooks running.

Issue with Java Shutdown hook

2 Answers2