import java.util.Random;

public class Start {

    public static boolean value;

    public static void main(String[] args){
        Thread thread = new Thread(){
            @Override
            public void run(){
                random();
            }
        };
        thread.start();
        while(true){
            if(value) System.out.println("Done");
        }
    }

    public static void random(){
        while(true){
            value = new Random().nextInt(5) == 0;
        }
    }

}

while(true){
System.out.print(""); //Modification
    if(value) System.out.println("Done");
}