...
Icon tree = new ImageIcon("Tree.GIF");
Icon tent = new ImageIcon("Tent.GIF");

button = new JButton ("Icon Button", tree);
button.setRolloverIcon(tent);
...

...
// define a text field and set its font
text = new JTextField("Default text", 10);
text.setFont ( new Font ("Times.Roman, Font.PLAIN, 12) );

// define a check box
checkBold = new JCheckBox("Bold");

[... insert code to add these to a window ... ]

// set up an event handler
CheckBoxHandler handler = new CheckBoxHandler();
checkBold.addItemListener(handler);

[... insert code to open the window etc. ...]

// the event handler class
private class CheckBoxHandler implements ItemListener
{
   private int valueText = Font.PLAIN;

   public void itemStateChanged (ItemEvent e)
   { if (e.getSource() == checkBold)
     {
       if (e.getStateChange() == ItemEvent.SELECTED) { valueText = Font.BOLD; }
       else { valueText = Font.PLAIN; }

       text.setFont( new Font (Times.Roman, valueText, 12) );
       text.repaint();
     }
   }
}
...

// Make two radio buttons with initial values of true and false

button1 = new JRadioButton("Button 1", true);
button2 = new JRadioButton("Button 2", false);

// Add these two radio buttons to the same group so that when
// one is switched on, the other automatically switches off
radioGroup = new ButtonGroup();
radioGroup.add(button1);
radioGroup.add(button2);

// In an ItemListener event handler examine
// e.getSource() == button1 or button2
// to determine which button was pushed.

import [...]

public class ComboBoxTest extends JFrame
{
	private JComboBox images;
	private JLabel label;
	
	private String names[] = { "Tent.gif", "Tree.gif" };
	private Icon icons[] = { new ImageIcon(names[0]), new ImageIcon(names[1]) };

  public ComboBoxTest()
  {
   super ("Combo Boxed");

   Container c = getContentPane();
   c.setLayout(new FlowLayout());
   c.setBackground(Color.white);

   images = new JComboBox (names); // add the text entries for the pull down menu
   images.setMaximumRowCount(2);   // maximum length of the menu bar that drops down before a scroll bar is added
   
   images.addItemListener ( new ItemListener() {
     public void itemStateChanged (ItemEvent e)
     { label.setIcon(icons[ images.getSelectedIndex() ]); } } );
   
      label = new JLabel(icons[0]);
   
      c.add(images);
      c.add(label);
  }
   
  public static void main (String args[])
  {
      ComboBoxTest app = new ComboBoxTest();
      app.addWindowListener( new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } } );
      app.setSize (200,75);
      app.setVisible(true);
  }
}

import [...]

public class MouseEventsTest extends JFrame implements MouseListener, MouseMotionListener
{
	private JLabel statusBar;
	
	public MouseEventsTest()
	{
		super ("Mouse Events");
		statusBar = new JLabel();
		getContentPane().add(statusBar, BorderLayout.SOUTH);

      addMouseListener(this);
      addMouseMotionListener(this);
   }
   
   // MouseListener events...
   public void mouseClicked (MouseEvent e)
   { statusBar.setText("Click at [" + e.getX() + ", " + e.getY() + "]"); }
   
   public void mousePressed (MouseEvent e)
   { statusBar.setText("Press at [" + e.getX() + ", " + e.getY() + "]"); }

   public void mouseReleased (MouseEvent e)
   { statusBar.setText("Release at [" + e.getX() + ", " + e.getY() + "]"); }

   public void mouseEntered (MouseEvent e)
   { statusBar.setText("Mouse inside window"); }

   public void mouseExited (MouseEvent e)
   { statusBar.setText("Mouse outside window"); }
   
   // MouseMotionListener events...
   public void mouseDragged (MouseEvent e)
   { statusBar.setText("Drag at [" + e.getX() + ", " + e.getY() + "]"); }
   
   public void mouseMoved (MouseEvent e)
   { statusBar.setText("Moved at [" + e.getX() + ", " + e.getY() + "]"); }
   
   public static void main (String args[])
   {
      MouseEventsTest app = new MouseEventsTest();
      app.addWindowListener( new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } } );
      app.setSize (250,100);
      app.setVisible(true);
   }
}

The text is updated as the different mouse handlers are invoked. This one needs to be executed to be properly understood.

Once you've understood what is happening, read up on the KeyListener and see if you can use it.