import java.awt.*;    import java.awt.event.*;    import javax.swing.*;        public class lc4 implements ActionListener   {        int n=13;                JFrame jf=new JFrame("Example");                    JTextField tf1=new JTextField(5);        JTextField tf2=new JTextField(15);                Label l=new Label("Please Input A Number:");                JButton b=new JButton("Close");            public static void main(String[] args) {            lc4 that=new lc4();            that.go();        }                public void go(){            jf.getContentPane().setLayout(new FlowLayout());                        l.setBackground(Color.yellow);            tf1.setBackground(Color.green);            tf2.setBackground(Color.red);            b.setBackground(Color.gray);                        jf.getContentPane().add(l);            jf.getContentPane().add(tf1);            jf.getContentPane().add(tf2);            jf.getContentPane().add(b);                        tf1.addActionListener(this);            tf2.addActionListener(this);            b.addActionListener(this);                        jf.pack();            jf.setVisible(true);        }        public void actionPerformed(ActionEvent e) {                        if(n==Integer.valueOf(tf1.getText())){                tf2.setText("U R Right!");            }            else if(n<Integer.valueOf(tf1.getText())){                tf2.setText("Bigger!");            }            else{                tf2.setText("Smaller!");            }                        if((JButton)e.getSource()==b){                System.exit(0);            }        }            }