Date

package javaapplication2;
import java.util.Date;

public class JavaApplication2 {

    public static void main(String[] args) {

        Date data=new Date();
        int godzina=data.getHours();
        int minuta=data.getMinutes();
        int sekunda=data.getSeconds();

        if (godzina < 10)
            System.out.print("0" + godzina + ":");
        else
            System.out.print(godzina + ":");

        if (minuta < 10)
            System.out.print("0" + minuta + ":");
        else
            System.out.print(minuta + ":");

        if (sekunda < 10)
            System.out.print("0" + sekunda + ":");
        else
            System.out.println(sekunda);

    }
}