import java.util.*;import java.io.*;public class BS{ public static void main(String[] arg) { String[] cmd = {"cmd /c cls"}; Properties sysProps = System.getProperties(); Enumeration enum = sysProps.propertyNames(); while (enum.hasMoreElements()) { String k = (String)enum.nextElement(); if (k.equals("os.name")) { if (sysProps.getProperty(k).substring(0,3).equals("Win")) { System.out.println("System Windows"); try { Runtime.getRuntime().exec(cmd); } catch(IOException e) { System.out.println(e.getMessage()); } } } } }}