how to set the value of textfield constant

Java Set the value of textfield constant:

import javax.swing.*;

class  ConstantText{
    public static void main(String[] args){
        JFrame f=new JFrame();
        f.setLayout(null);
        JTextField text=new JTextField(20);
        text.setText("Hello");
        text.setEditable(false);
   text.setBounds(10,10,100,20);
   f.add(text);
   f.setVisible(true);
   f.setSize(300,100);
   }
}