Sample code shows how to launch an Impress slide show and stop it. Uses Timer routines in another gist. Works on Windows 10 and Linux Mint 19.

ImpressShowRunner_StartStopShows.java

	public void startShowPlaying( String sImpress, String sOptions, String sShowPath ) {
		
		if ( bShowRunning ) {
			
			System.out.println("startShowPlaying already running");
			return;
		}
		String cmdString = sImpress +" "+sOptions+" "+sShowPath;
		try {
			pShowProcess = Runtime.getRuntime().exec( cmdString );
			System.out.println("startShowPlaying show started");
			bShowRunning = true;
			if ( bTimerRunning ) {
				stopTimer();
			}
			startTimer( 5000 );
		} catch (Exception ex ) {
			System.out.println("startShowPlaying exception");
		}

	}
	
	public void stopShow() {
		if ( !bShowRunning ) {
			System.out.println("stopShow show not running");
			return;
		}
		// we cannot use destroy() since that would leave the Impress show
		// in a bad state. So all we can do is wait on the user to stop the
		// show and then clean up.
		
		try {
			// stop the mouse clicks
			stopTimer();
			System.out.println("stopShow waiting for you to stop the show");
			pShowProcess.waitFor();
			System.out.println("stopShow show not running");
			bShowRunning = false;
		} catch (Exception ex ) {
			System.out.println("stopShow exception");
			bShowRunning = false; // try to clean up
		}
	}