How to Keep a Program opened from a Java Runtime.exec(command) Always on Top
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We have a full screen java program running on a Linux box.  The program is always running, and is the primary reason for the Linux box existing.

We have a bunch of PDF Help files for the program that can be opened through a dropdown menu.  When a user clicks one of the help menu items we open XPDF through

        final Runtime rt = Runtime.getRuntime();
        final String cmd = "runxpdf.sh";
        rt.exec(cmd);

This all works fine except that if the user clicks on our program while the XPDF viewer is running it will fall behind our full screen program display.

What we'd like to be able to do is to keep the XPDF program always on top until it is closed.  Is this possible to do through executing a program from Java?