ImageIcon example

 import javax.swing.*;
import java.awt.*; // layout
// Step 1
import java.awt.event.*; //ActionListener

public class TongjinFrame extends JFrame
         /*Step 2*/  implements ActionListener{
  
  private JLabel lblPic;
  private ImageIcon imgTJ, imgIvan;
  
  private JButton btnChange;
  
  public TongjinFrame(){
    
    imgTJ = new ImageIcon("tongjin.jpg");
    imgIvan = new ImageIcon("ivan.jpg");
        
    lblPic = new JLabel(imgTJ);
    
    btnChange = new JButton("Change");
    
    getContentPane().add(lblPic);
    getContentPane().add(btnChange, "South");
    
    // Step 4
    btnChange.addActionListener(this);
  }
  
  // Step 3:
  public void actionPerformed(ActionEvent ev){
    lblPic.setIcon(imgIvan);
  } //end actionPerformed
  
}//end class