How to Get the State of JCheckBox in Java Swing

In this tutorial, we are going to see How to get the state of JCheckBox in Java Swing . JCheckBox is a Swing component that represents an element that shows a selected or unselected state. The user can change this state by clicking on the component’s checkbox.

A standard JCheckBox component contains a checkbox and a label that describes the purpose of the checkbox.

JCheckBox can generate an ActionListener interface. When we click on the checkbox, actionPerformed() method is called.
 

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Java Program to Get the State of JCheckBox:

The following code shows how to get the state of a JCheckBox. The method to get the state is JCheckBox.isSelected() which returns a Boolean value.

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

public class StateOfCheckBox extends JFrame 
{
    public StateOfCheckBox() throws HeadlessException {
        initGUI();
    }

    private void initGUI() {
        setSize(200, 100);
        setLayout(new FlowLayout(FlowLayout.LEFT));

        // create a checkbox with a label
        JCheckBox cb = new JCheckBox("Test");
        cb.setSelected(true);

        cb.addActionListener(new ActionListener(){
          public void actionPerformed(ActionEvent ae) { 
            // Get the state of the checkbox
            boolean state = cb.isSelected();
            if (state) {
               System.out.println("Check box is selected.");
            } else {
               System.out.println("Checkbox is not selected.");
            }
          }
        });
        //add the checkbox to the frame
        getContentPane().add(cb);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new StateOfCheckBox().setVisible(true);
            }
        });
    }
}

Output:

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