menentukan umur( GUI)

import javax.swing.JOptionPane;
class menentukan_umur_anak2
{
public static void main(String[] args) throws Exception
{
int u;
String umur;
umur=JOptionPane.showInputDialog("Umur :");
u=Integer.parseInt(umur);
if ((u>=0)&&(u<=4))
{
JOptionPane.showMessageDialog(null,"Balita");
}
else
if ((u>=5)&&(u<=13))
{
JOptionPane.showMessageDialog(null,"Anak - Anak");
}
else
if ((u>=14)&&(u<=19))
{
JOptionPane.showMessageDialog(null,"Remaja");
}
else
if ((u>=20)&&(u<=35))
{
JOptionPane.showMessageDialog(null,"Dewasa");
}
else
if ((u>=36)&&(u<=60))
{
JOptionPane.showMessageDialog(null,"Tua");
}
else
if (u>=61)
{
JOptionPane.showMessageDialog(null,"Lansia");
}
System.exit(0);
}
}