Belajar JAVA: Menginput Data dan Mencetaknya (Versi GUI)

import javax.swing.*;

public class inputdarikeyboard2{
    public static void main(String[] args) {
        String NIM="", Nama="";
        byte    nilAbsen=0, nilTugas=0, nilUTS=0, nilUAS=0;
       
    try{
        NIM=JOptionPane.showInputDialog("NIM : ");
        Nama=JOptionPane.showInputDialog("Nama : ");
        nilAbsen=Byte.parseByte(JOptionPane.showInputDialog("Nilai Absen : "));
        nilTugas=Byte.parseByte(JOptionPane.showInputDialog("Nilai Tugas : "));
        nilUTS=Byte.parseByte(JOptionPane.showInputDialog("Nilai UTS : "));
        nilUAS=Byte.parseByte(JOptionPane.showInputDialog("NilaiUAS : "));
        }
    catch(Exception e) {
        System.out.println ("Error : "+e);
    }
   
    System.out.println ("==============================================");
    System.out.println ("\t\t Cetak Data Mahasiswa            ");
    System.out.println ("==============================================");
    System.out.println ("NIM\t\t: "+NIM);
    System.out.println ("Nama\t\t: "+Nama);
    System.out.println ("Nilai Absen\t: "+nilAbsen);
    System.out.println ("Nilai Tugas\t: "+nilTugas);
    System.out.println ("Nilai UTS    : "+nilUTS);
    System.out.println ("Nilai UAS    : "+nilUAS);
    System.out.println ("==============================================");
    }
    }