Issues with Designer Hook shutdown method

I am trying to do some cleanup tasks in the DesignerHook shutdown method.
Basically trying to delete some temporary files that were created in my custom component.

Following is what I want to do -

String userHomeDirectory = System.getProperty(“user.home”);

    File dir = new File(userHomeDirectory);
    FileFilter fileFilter = new WildcardFileFilter(".mymodule*");
    File[] files = dir.listFiles(fileFilter);
    //delete the files that start with name above
    for (int i = 0; i < files.length; i++) {
    	try {
	} catch (IOException e) {
		// TODO Auto-generated catch block

This works perfectly when written in ClientHook shutdown method.
However is not working from DesignerHook shutdown method.

When some one runs the component from designer, temporary files get created but I believe Designer Hook shutdown is not getting called and temporary files are not deleted.

Tested this on 7.9.4 , 7.9.5 and 7.9.6
Java version 7.8.0_161

Appreciate any help in this regard.