How to wait for a method to finish completely before proceeding?

Question

the coding below will run OSK (On Screen Keyboard) process after killProcess() kills it, previously it does not pop up before I added the Thread.sleep for 1 second. So is there any way that I can make sure killProcess() is fully executed before it start the OSK process without Thread.sleep for one second?? something that is not timed-based, a code that will run killProcess() completely before going into the next line. Sorry for any confusion and thanks for reading! Hope someone is willing to help me with this one.

public static void main(String... args) {
    try {
        killProcess();

        try {
            Thread.sleep(1000);
        } catch (InterruptedException ex) {
            Thread.currentThread().interrupt();
        }

        Runtime.getRuntime().exec("c:\\Temp\\osk.exe");

    } catch (Exception ex) {
        ex.printStackTrace();
    }

}

public static void killProcess() throws Exception {

    Runtime rt = Runtime.getRuntime();

    rt.exec("cmd.exe /c taskkill " + "osk.exe");

    Runtime.getRuntime().exec("taskkill /IM " + "osk.exe");

}

Answer 1

public static void main(String... args) {
    try {
        killProcess();
        Runtime.getRuntime().exec("c:\\Temp\\osk.exe");

    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

public static void killProcess() throws Exception {
    Runtime rt = Runtime.getRuntime();
    rt.exec("cmd.exe /c taskkill " + "osk.exe").waitFor();
    rt.exec("taskkill /IM " + "osk.exe").waitFor();
}

Runtime.exec(String) returns a Process , which has the waitFor() method. This will block the current Thread until the process has terminated.