A Java Program to Learn the use of Check Box ,Radio Button and Text Area.

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

class CheckRadio extends JFrame implements ActionListener
{
 //variables
 JCheckBox cb1, cb2;
 JRadioButton rb1, rb2;
 JTextArea ta;
 ButtonGroup bg;
 String msg="";

 CheckRadio()
 {
  //create the content pane
  Container c = getContentPane();

  //set flow layout to content pane
  c.setLayout(new FlowLayout());

  //create a text area with 10 rows and 20 chars per row
  ta = new JTextArea(10,20);

  //create two check boxes
  cb1 = new JCheckBox("Java", true);
  cb2 = new JCheckBox("J2EE");

  //create two radio buttons
  rb1 = new JRadioButton("Male", true);
  rb2 = new JRadioButton("Female");

  //create a button group and add the radio buttons to it
  bg = new ButtonGroup();
  bg.add(rb1);
  bg.add(rb2);

  //add the checkboxes, radio buttons, textarea to the container
  c.add(cb1);
  c.add(cb2);
  c.add(rb1);
  c.add(rb2);
  c.add(ta);

  //add action listeners. We need not add listener to text area
  //since the user clicks on the checkboxes or radio buttons only
  cb1.addActionListener(this);
  cb2.addActionListener(this);
  rb1.addActionListener(this);
  rb2.addActionListener(this);
 
  //close the frame upon clicking
  setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 }

 public void actionPerformed(ActionEvent ae)
 {
  //know which components are selected by user
  if(cb1.getModel().isSelected()) msg+="\nJava";
  if(cb2.getModel().isSelected()) msg+="\nJ2EE";  
  if(rb1.getModel().isSelected()) msg+="\nMale";
  else msg+="\nFemale";
  //display the selected message in text area
  ta.setText(msg);

  //reset the message to empty string
  msg="";
  }

 public static void main(String args[])
 {
  //create frame
  CheckRadio cr = new CheckRadio();
  cr.setTitle("My checkboxes and Radio buttons");
  cr.setSize(500,400);
  cr.setVisible(true);
 }
}