The document outlines the functionality and usage of the JCheckbox class in Java Swing, detailing its constructors and how to manage its state. It provides an example program demonstrating the initialization of multiple checkboxes with associated item listeners. The implementation showcases user interaction where the state of checkboxes updates a text field based on selections.

1. JAVA SWING
JCheckBox , JRadioButton, JComboBox

2. Check Boxes
The JCheckBox class, which provides the functionality of a check
box, is a concrete implementation of AbstractButton.
 Its immediate superclass is JToggleButton, which provides support
for two-state buttons.
 Some of its constructors are shown here:
 JCheckBox(Icon i)
 JCheckBox(Icon i, boolean state)
 JCheckBox(String s)
 JCheckBox(String s, boolean state)
 JCheckBox(String s, Icon i)
 JCheckBox(String s, Icon i, boolean state)
Here, i is the icon for the button. The text is specified by s. If state is
true, the check box is initially selected. Otherwise, it is not.

3. METHOD FOR STATE OF THE CHECK BOX
The state of the check box can be changed via the
following method:
void setSelected(boolean state)
Here, state is true if the check box should be checked.

4. Example Program for JCheckBox
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
/*<applet code="JCheckBoxDemo" width=400 height=50> </applet>*/
public class JCheckBoxDemo extends JApplet implements
ItemListener
{
JTextField jtf;
JCheckBox cb1,cb2,cb3;
public void init()
{
Container contentPane = getContentPane();

5. Example Program for Check Box
contentPane.setLayout(new FlowLayout());
cb1=new JCheckBox("C",true);
cb2 = new JCheckBox(“C++”);
cb3=new JCheckBox(new ImageIcon("java5.png"));
cb1.addItemListener(this);
contentPane.add(cb1);
cb2.addItemListener(this);
contentPane.add(cb2);
cb3.addItemListener(this);
contentPane.add(cb3);
jtf= new JTextField(15);
contentPane.add(jtf);
}

6. Example Program for Check Box
public void itemStateChanged(ItemEvent ie)
{
if(ie.getItemSelectable()==cb1)
{
jtf.setText("C");
}
if(ie.getItemSelectable()==cb2)
{
jtf.setText("C++");
}

7. Example Program for Check Box
if(ie.getItemSelectable()==cb3)
{
jtf.setText("Java");
}
}
}

8. Output for Check Box