Programing with Java1

public class Latihan1 {
    public static void main(String[]args){
       
        for(int menu=0;menu!=4;){

        menu = Integer.parseInt(JOptionPane.showInputDialog
                ("Pilihan Menu : "
                +"\n1. Luas Persegi Panjang"
                +"\n2. Luas Persegi"

                +"\n3. Luas Segitiga"
                +"\n4. Keluar"));

        switch(menu){
            case 1:
                try{
                int P, L, Luas;
                P = Integer.parseInt(JOptionPane.showInputDialog("Masukkan Panjang !"));
                L = Integer.parseInt(JOptionPane.showInputDialog("Masukkan Lebar !"));
                Luas = P*L;
                JOptionPane.showMessageDialog(null,"Luas Persegi Panjang = "+Luas);
                }catch(Exception e){
                    JOptionPane.showMessageDialog(null, "Masukkan angka bro");
                }
                break;
            case 2:
                int S, Luas1;
                S = Integer.parseInt(JOptionPane.showInputDialog("Masukkan Sisi !"));
                Luas1 = S*S;
                JOptionPane.showMessageDialog(null,"Luas Bujur Sangkar = "+Luas1);
                break;

            case 3:
                float A, T, Luas2;
                A = Float.parseFloat(JOptionPane.showInputDialog("Masukkan Alas"));
                T = Float.parseFloat(JOptionPane.showInputDialog("Masukkan Tinggi"));
                Luas2 = (A*T)/2;
                JOptionPane.showMessageDialog(null,"Luas Segitiga = "+Luas2);
                break;

            case 4:
                JOptionPane.showMessageDialog(null,"Terima Kasih");
                break;

            default:
                JOptionPane.showMessageDialog(null,"input salah");
                break;
            }
        }

    }
}