Simple Calculator Program in Java Using AWT

Hello Friends, Welcome to my new tutorial about creating a simple calculator program in Java using AWT. In this tutorial, we will see how to design and code the GUI calculator application using Java AWT.

Using this Simple Calculator Application in Java AWT, we will be able to do basic arithmetic operations like addition, subtraction, Multiplication, Division, as well as finding the Square, Square root, and reciprocal of any number.You can download the project’s source code by navigating to the end of this tutorial.

Before starting this tutorial, I assume that you have the basic concept of Java AWT Components and Java Button Click Event, which means what should be the response of a Java Button when we click on it. If you already know about these, it would be a lot easier for you to understand the tutorial.

I will use NetBeans IDE for Developing My Calculator Project, but you can use any IDE like Eclipse, IntelliJ Idea, or simply any text editor like Notepad. It doesn’t matter whatever IDE or text editor you will use for development. The coding and logic will be the same.

So without further ado, let’s start our tutorial Simple calculator program in Java using AWT.

Also Read – Simple Calculator Program in Java Using Swing

Table of Contents

Creating a New Project in NetBeans

So, first of all, we need to create a new project in NetBeans. Follow these steps to create a new project.

Open the NetBeans IDE, click on the File menu, and select New Project.

Simple Calculator Program in Java Using AWT – Fig – 1

After you click on the New Project, a new window will be opened where you have to select the Project type as “Java with Ant” and then select the Java Application.
Then click on the Next button to proceed.

Again, a new window will be opened where you have to give the name of your project (AwtCalculator in this Example) and tick mark in the “Create Main Class” checkbox.
Then click on the Finish button to finish creating the Project.

Creating Display Window/Frame

In this step, we will create a display window, or we can say Frame for our calculator.

First of all, import all the necessary packages, which are,

import java.awt.*;
import java.awt.event.*;

1 2	import java.awt.; import java.awt.event.;

We need to import the java.awt.event package too, because we will deal with button click events in our program.
Next, Create an object of the Frame class and then set some of its properties like its size, location, layout, Background color, Visibility, and the close operation using the methods of the Frame class.

package awtcalculator;
//importing all necessary packages
import java.awt.*;
import java.awt.event.*;

public class AwtCalculator {

    //Creating object of Frame Class
    Frame frame=new Frame("Calculator");
    
    //Creating Constructor of the Class
    AwtCalculator(){

        prepareFrame();
        

    }
    
     public void prepareFrame(){

         //Setting Frame's Property
        frame.setSize(300,490);
        frame.setLayout(null);
        frame.setBackground(new Color(12,12,93));
        frame.setResizable(false);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
        frame.addWindowListener(
                new WindowAdapter(){
                    public void windowClosing(WindowEvent e) { System.exit(0); }
                }
        );
    }
    public static void main(String[] args) {
       
        //Creating object of the AwtCalculator class which will call the constructor
        AwtCalculator calculator = new AwtCalculator();
    }
    
}

package awtcalculator;

//importing all necessary packages

import java.awt.*;

import java.awt.event.*;

public class AwtCalculator {

//Creating object of Frame Class

Frame frame=new Frame("Calculator");

//Creating Constructor of the Class

AwtCalculator(){

prepareFrame();

}

public void prepareFrame(){

//Setting Frame's Property

frame.setSize(300,490);

frame.setLayout(null);

frame.setBackground(new Color(12,12,93));

frame.setResizable(false);

frame.setLocationRelativeTo(null);

frame.setVisible(true);

frame.addWindowListener(

new WindowAdapter(){

public void windowClosing(WindowEvent e) { System.exit(0); }

}

);

}

public static void main(String[] args) {

//Creating object of the AwtCalculator class which will call the constructor

AwtCalculator calculator = new AwtCalculator();

}

Now Run your program.

As you can see, we have successfully created our display window, and the next thing we have to do is add components to it.

Adding Components to Frame/Window

In this step, we will create the object of all the components that we want to add to our Frame/Window, which are,

- Buttons from 0 to 9.
- One clear Button and a delete button.
- Buttons for arithmetic operations.
- One button for negative Calculations.
- A text field for displaying the result.
- Two checkboxes for switching between on and off.
- One label for displaying the calculation.
After creating the object of all the components, we will set some of the properties of each component, like setting their size, location, and some other properties.
After setting their properties, we will finally add them to the frame(Window) using the add() method.

package awtcalculator;
//importing all necessary packages
import java.awt.*;
import java.awt.event.*;

public class AwtCalculator {

    //Creating object of Frame Class
    Frame frame=new Frame("Calculator");
    
    //Creating objects of all the components
    Label label=new Label();
    TextField textField=new TextField();
    CheckboxGroup checkboxGroup=new CheckboxGroup();
    Checkbox onCheckbox=new Checkbox("On",checkboxGroup,true);
    Checkbox offCheckbox=new Checkbox("Off",checkboxGroup,false);
    Button buttonZero = new Button("0");
    Button buttonOne = new Button("1");
    Button buttonTwo = new Button("2");
    Button buttonThree = new Button("3");
    Button buttonFour = new Button("4");
    Button buttonFive = new Button("5");
    Button buttonSix = new Button("6");
    Button buttonSeven = new Button("7");
    Button buttonEight = new Button("8");
    Button buttonNine = new Button("9");
    Button buttonDot = new Button(".");
    Button buttonClear = new Button("CLR");
    Button buttonDelete = new Button("DEL");
    Button buttonEqual = new Button("=");
    Button buttonNegative = new Button("(-)");
    Button buttonMul = new Button("x");
    Button buttonDiv = new Button("/");
    Button buttonPlus = new Button("+");
    Button buttonMinus = new Button("-");
    Button buttonSquare = new Button("x\u00B2");
    Button buttonReciprocal = new Button("1/x");
    Button buttonSqrt = new Button("\u221A");

    
    //Creating Constructor of the Class
    AwtCalculator(){

        prepareFrame();
        addComponents();
        

    }
    
     public void prepareFrame(){

         //Setting Frame's Property
        frame.setSize(300,490);
        frame.setLayout(null);
        frame.setBackground(new Color(12,12,93));
        frame.setResizable(false);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
        frame.addWindowListener(
                new WindowAdapter(){
                    public void windowClosing(WindowEvent e) { System.exit(0); }
                }
        );
    }
     
      public void addComponents(){

          //Setting properties of the Components and adding them to the Frame
        label.setBounds(10, 40, 200, 20);
        label.setForeground(Color.white);
        label.setFont(new Font("Arial",Font.BOLD,15));
        frame.add(label);

        textField.setBounds(15,60,270,35);
        textField.setFont(new Font("Arial",Font.BOLD,20));
        textField.setEditable(false);
        frame.add(textField);


        onCheckbox.setBounds(15, 100, 60, 40);
        onCheckbox.setFont(new Font("Arial", Font.BOLD, 14));
        onCheckbox.setBackground(new Color(12,12,93));
        onCheckbox.setForeground(Color.white);
        onCheckbox.setFocusable(false);
        frame.add(onCheckbox);

        offCheckbox.setBounds(15, 125, 60, 40);
        offCheckbox.setFont(new Font("Arial", Font.BOLD, 14));
        offCheckbox.setBackground(new Color(12,12,93));
        offCheckbox.setForeground(Color.white);
        offCheckbox.setFocusable(false);
        frame.add(offCheckbox);

        buttonSeven.setBounds(15, 230, 60, 40);
        buttonSeven.setFont(new Font("Arial", Font.BOLD, 20));
        buttonSeven.setFocusable(false);
        frame.add(buttonSeven);

        buttonEight.setBounds(85, 230, 60, 40);
        buttonEight.setFont(new Font("Arial", Font.BOLD, 20));
        buttonEight.setFocusable(false);
        frame.add(buttonEight);

        buttonNine.setBounds(155, 230, 60, 40);
        buttonNine.setFont(new Font("Arial", Font.BOLD, 20));
        buttonNine.setFocusable(false);
        frame.add(buttonNine);

        buttonFour.setBounds(15, 290, 60, 40);
        buttonFour.setFont(new Font("Arial", Font.BOLD, 20));
        buttonFour.setFocusable(false);
        frame.add(buttonFour);

        buttonFive.setBounds(85, 290, 60, 40);
        buttonFive.setFont(new Font("Arial", Font.BOLD, 20));
        buttonFive.setFocusable(false);
        frame.add(buttonFive);

        buttonSix.setBounds(155, 290, 60, 40);
        buttonSix.setFont(new Font("Arial", Font.BOLD, 20));
        buttonSix.setFocusable(false);
        frame.add(buttonSix);

        buttonOne.setBounds(15, 350, 60, 40);
        buttonOne.setFont(new Font("Arial", Font.BOLD, 20));
        buttonOne.setFocusable(false);
        frame.add(buttonOne);

        buttonTwo.setBounds(85, 350, 60, 40);
        buttonTwo.setFont(new Font("Arial", Font.BOLD, 20));
        buttonTwo.setFocusable(false);
        frame.add(buttonTwo);

        buttonThree.setBounds(155, 350, 60, 40);
        buttonThree.setFont(new Font("Arial", Font.BOLD, 20));
        buttonThree.setFocusable(false);
        frame.add(buttonThree);

        buttonDot.setBounds(155, 410, 60, 40);
        buttonDot.setFont(new Font("Arial", Font.BOLD, 20));
        buttonDot.setFocusable(false);
        frame.add(buttonDot);

        buttonZero.setBounds(15, 410, 60, 40);
        buttonZero.setFont(new Font("Arial", Font.BOLD, 20));
        buttonZero.setFocusable(false);
        frame.add(buttonZero);

        buttonNegative.setBounds(85,410,60,40);
        buttonNegative.setFont(new Font("Arial",Font.BOLD,20));
        buttonNegative.setFocusable(false);
        frame.add(buttonNegative);

        buttonEqual.setBounds(225, 350, 60, 100);
        buttonEqual.setFont(new Font("Arial", Font.BOLD, 20));
        buttonEqual.setBackground(new Color(72, 231, 172));
        buttonEqual.setFocusable(false);
        frame.add(buttonEqual);

        buttonDiv.setBounds(225, 110, 60, 40);
        buttonDiv.setFont(new Font("Arial", Font.BOLD, 20));
        buttonDiv.setBackground(new Color(72, 231, 172));
        buttonDiv.setFocusable(false);
        frame.add(buttonDiv);

        buttonSqrt.setBounds(15, 170, 60, 40);
        buttonSqrt.setFont(new Font("Arial", Font.BOLD, 18));
        buttonSqrt.setFocusable(false);
        frame.add(buttonSqrt);

        buttonMul.setBounds(225, 230, 60, 40);
        buttonMul.setFont(new Font("Arial", Font.BOLD, 20));
        buttonMul.setBackground(new Color(72, 231, 172));
        buttonMul.setFocusable(false);
        frame.add(buttonMul);

        buttonMinus.setBounds(225, 170, 60, 40);
        buttonMinus.setFont(new Font("Arial", Font.BOLD, 20));
        buttonMinus.setBackground(new Color(72, 231, 172));
        buttonMinus.setFocusable(false);
        frame.add(buttonMinus);

        buttonPlus.setBounds(225, 290, 60, 40);
        buttonPlus.setFont(new Font("Arial", Font.BOLD, 20));
        buttonPlus.setBackground(new Color(72, 231, 172));
        buttonPlus.setFocusable(false);
        frame.add(buttonPlus);

        buttonSquare.setBounds(85, 170, 60, 40);
        buttonSquare.setFont(new Font("Arial", Font.BOLD, 20));
        buttonSquare.setFocusable(false);
        frame.add(buttonSquare);

        buttonReciprocal.setBounds(155, 170, 60, 40);
        buttonReciprocal.setFont(new Font("Arial", Font.BOLD, 15));
        buttonReciprocal.setFocusable(false);
        frame.add(buttonReciprocal);

        buttonDelete.setBounds(155, 110, 60, 40);
        buttonDelete.setFont(new Font("Arial", Font.BOLD, 12));
        buttonDelete.setBackground(Color.red);
        buttonDelete.setForeground(Color.white);
        buttonDelete.setFocusable(false);
        frame.add(buttonDelete);

        buttonClear.setBounds(85, 110, 60, 40);
        buttonClear.setFont(new Font("Arial", Font.BOLD, 12));
        buttonClear.setBackground(Color.red);
        buttonClear.setForeground(Color.white);
        buttonClear.setFocusable(false);
        frame.add(buttonClear);



    }
    public static void main(String[] args) {
       
        //Creating object of the AwtCalculator class which will call the constructor
        AwtCalculator calculator = new AwtCalculator();
    }
    
}

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package awtcalculator;

//importing all necessary packages

import java.awt.*;

import java.awt.event.*;

public class AwtCalculator {

//Creating object of Frame Class

Frame frame=new Frame("Calculator");

//Creating objects of all the components

Label label=new Label();

TextField textField=new TextField();

CheckboxGroup checkboxGroup=new CheckboxGroup();

Checkbox onCheckbox=new Checkbox("On",checkboxGroup,true);

Checkbox offCheckbox=new Checkbox("Off",checkboxGroup,false);

Button buttonZero = new Button("0");

Button buttonOne = new Button("1");

Button buttonTwo = new Button("2");

Button buttonThree = new Button("3");

Button buttonFour = new Button("4");

Button buttonFive = new Button("5");

Button buttonSix = new Button("6");

Button buttonSeven = new Button("7");

Button buttonEight = new Button("8");

Button buttonNine = new Button("9");

Button buttonDot = new Button(".");

Button buttonClear = new Button("CLR");

Button buttonDelete = new Button("DEL");

Button buttonEqual = new Button("=");

Button buttonNegative = new Button("(-)");

Button buttonMul = new Button("x");

Button buttonDiv = new Button("/");

Button buttonPlus = new Button("+");

Button buttonMinus = new Button("-");

Button buttonSquare = new Button("x\u00B2");

Button buttonReciprocal = new Button("1/x");

Button buttonSqrt = new Button("\u221A");

//Creating Constructor of the Class

AwtCalculator(){

prepareFrame();

addComponents();

}

public void prepareFrame(){

//Setting Frame's Property

frame.setSize(300,490);

frame.setLayout(null);

frame.setBackground(new Color(12,12,93));

frame.setResizable(false);

frame.setLocationRelativeTo(null);

frame.setVisible(true);

frame.addWindowListener(

new WindowAdapter(){

public void windowClosing(WindowEvent e) { System.exit(0); }

}

);

}

public void addComponents(){

//Setting properties of the Components and adding them to the Frame

label.setBounds(10, 40, 200, 20);

label.setForeground(Color.white);

label.setFont(new Font("Arial",Font.BOLD,15));

frame.add(label);

textField.setBounds(15,60,270,35);

textField.setFont(new Font("Arial",Font.BOLD,20));

textField.setEditable(false);

frame.add(textField);

onCheckbox.setBounds(15, 100, 60, 40);

onCheckbox.setFont(new Font("Arial", Font.BOLD, 14));

onCheckbox.setBackground(new Color(12,12,93));

onCheckbox.setForeground(Color.white);

onCheckbox.setFocusable(false);

frame.add(onCheckbox);

offCheckbox.setBounds(15, 125, 60, 40);

offCheckbox.setFont(new Font("Arial", Font.BOLD, 14));

offCheckbox.setBackground(new Color(12,12,93));

offCheckbox.setForeground(Color.white);

offCheckbox.setFocusable(false);

frame.add(offCheckbox);

buttonSeven.setBounds(15, 230, 60, 40);

buttonSeven.setFont(new Font("Arial", Font.BOLD, 20));

buttonSeven.setFocusable(false);

frame.add(buttonSeven);

buttonEight.setBounds(85, 230, 60, 40);

buttonEight.setFont(new Font("Arial", Font.BOLD, 20));

buttonEight.setFocusable(false);

frame.add(buttonEight);

buttonNine.setBounds(155, 230, 60, 40);

buttonNine.setFont(new Font("Arial", Font.BOLD, 20));

buttonNine.setFocusable(false);

frame.add(buttonNine);

buttonFour.setBounds(15, 290, 60, 40);

buttonFour.setFont(new Font("Arial", Font.BOLD, 20));

buttonFour.setFocusable(false);

frame.add(buttonFour);

buttonFive.setBounds(85, 290, 60, 40);

buttonFive.setFont(new Font("Arial", Font.BOLD, 20));

buttonFive.setFocusable(false);

frame.add(buttonFive);

buttonSix.setBounds(155, 290, 60, 40);

buttonSix.setFont(new Font("Arial", Font.BOLD, 20));

buttonSix.setFocusable(false);

frame.add(buttonSix);

buttonOne.setBounds(15, 350, 60, 40);

buttonOne.setFont(new Font("Arial", Font.BOLD, 20));

buttonOne.setFocusable(false);

frame.add(buttonOne);

buttonTwo.setBounds(85, 350, 60, 40);

buttonTwo.setFont(new Font("Arial", Font.BOLD, 20));

buttonTwo.setFocusable(false);

frame.add(buttonTwo);

buttonThree.setBounds(155, 350, 60, 40);

buttonThree.setFont(new Font("Arial", Font.BOLD, 20));

buttonThree.setFocusable(false);

frame.add(buttonThree);

buttonDot.setBounds(155, 410, 60, 40);

buttonDot.setFont(new Font("Arial", Font.BOLD, 20));

buttonDot.setFocusable(false);

frame.add(buttonDot);

buttonZero.setBounds(15, 410, 60, 40);

buttonZero.setFont(new Font("Arial", Font.BOLD, 20));

buttonZero.setFocusable(false);

frame.add(buttonZero);

buttonNegative.setBounds(85,410,60,40);

buttonNegative.setFont(new Font("Arial",Font.BOLD,20));

buttonNegative.setFocusable(false);

frame.add(buttonNegative);

buttonEqual.setBounds(225, 350, 60, 100);

buttonEqual.setFont(new Font("Arial", Font.BOLD, 20));

buttonEqual.setBackground(new Color(72, 231, 172));

buttonEqual.setFocusable(false);

frame.add(buttonEqual);

buttonDiv.setBounds(225, 110, 60, 40);

buttonDiv.setFont(new Font("Arial", Font.BOLD, 20));

buttonDiv.setBackground(new Color(72, 231, 172));

buttonDiv.setFocusable(false);

frame.add(buttonDiv);

buttonSqrt.setBounds(15, 170, 60, 40);

buttonSqrt.setFont(new Font("Arial", Font.BOLD, 18));

buttonSqrt.setFocusable(false);

frame.add(buttonSqrt);

buttonMul.setBounds(225, 230, 60, 40);

buttonMul.setFont(new Font("Arial", Font.BOLD, 20));

buttonMul.setBackground(new Color(72, 231, 172));

buttonMul.setFocusable(false);

frame.add(buttonMul);

buttonMinus.setBounds(225, 170, 60, 40);

buttonMinus.setFont(new Font("Arial", Font.BOLD, 20));

buttonMinus.setBackground(new Color(72, 231, 172));

buttonMinus.setFocusable(false);

frame.add(buttonMinus);

buttonPlus.setBounds(225, 290, 60, 40);

buttonPlus.setFont(new Font("Arial", Font.BOLD, 20));

buttonPlus.setBackground(new Color(72, 231, 172));

buttonPlus.setFocusable(false);

frame.add(buttonPlus);

buttonSquare.setBounds(85, 170, 60, 40);

buttonSquare.setFont(new Font("Arial", Font.BOLD, 20));

buttonSquare.setFocusable(false);

frame.add(buttonSquare);

buttonReciprocal.setBounds(155, 170, 60, 40);

buttonReciprocal.setFont(new Font("Arial", Font.BOLD, 15));

buttonReciprocal.setFocusable(false);

frame.add(buttonReciprocal);

buttonDelete.setBounds(155, 110, 60, 40);

buttonDelete.setFont(new Font("Arial", Font.BOLD, 12));

buttonDelete.setBackground(Color.red);

buttonDelete.setForeground(Color.white);

buttonDelete.setFocusable(false);

frame.add(buttonDelete);

buttonClear.setBounds(85, 110, 60, 40);

buttonClear.setFont(new Font("Arial", Font.BOLD, 12));

buttonClear.setBackground(Color.red);

buttonClear.setForeground(Color.white);

buttonClear.setFocusable(false);

frame.add(buttonClear);

}

public static void main(String[] args) {

//Creating object of the AwtCalculator class which will call the constructor

AwtCalculator calculator = new AwtCalculator();

}

Now run your program.

As you can see that we have successfully added the components to our Frame/Window.
Now we have to add functionalities to our button so that some action should be performed when we click on a particular button.
- For this, we will implement the ActionListener interface in our class. If we implement the ActionListener interface in our class, we have to override its method actionPerformed() in that class.
- We have also created the checkboxes for switching between on and off. For this, we need to implement the ItemListener interface in our class. If we implement the ItemListener interface in our class, we have to override its method itemStateChanged() in that class.

Adding Functionalities

First of all, we will implement the ActionListener and ItemListener interface in our class, and then we will override their methods actionPerformed() and itemStateChanged() in that class.
Next, we will register ActionListener for all the buttons and ItemListener for checkboxes.
Next, all the actions that we want in response when a button is clicked will be coded inside the actionPerformed() method, and when a checkbox is clicked, its code will be coded inside the itemStateChanged() method.

package awtcalculator;
//importing all necessary packages
import java.awt.*;
import java.awt.event.*;

public class AwtCalculator implements ActionListener, ItemListener {

    //Declaring and Initializing variable for calculations
    double num1=0, num2=0, result=0;
    int calculation;
    
    //Creating object of Frame Class
    Frame frame=new Frame("Calculator");
    
    //Creating objects of all the components
    Label label=new Label();
    TextField textField=new TextField();
    CheckboxGroup checkboxGroup=new CheckboxGroup();
    Checkbox onCheckbox=new Checkbox("On",checkboxGroup,true);
    Checkbox offCheckbox=new Checkbox("Off",checkboxGroup,false);
    Button buttonZero = new Button("0");
    Button buttonOne = new Button("1");
    Button buttonTwo = new Button("2");
    Button buttonThree = new Button("3");
    Button buttonFour = new Button("4");
    Button buttonFive = new Button("5");
    Button buttonSix = new Button("6");
    Button buttonSeven = new Button("7");
    Button buttonEight = new Button("8");
    Button buttonNine = new Button("9");
    Button buttonDot = new Button(".");
    Button buttonClear = new Button("CLR");
    Button buttonDelete = new Button("DEL");
    Button buttonEqual = new Button("=");
    Button buttonNegative = new Button("(-)");
    Button buttonMul = new Button("x");
    Button buttonDiv = new Button("/");
    Button buttonPlus = new Button("+");
    Button buttonMinus = new Button("-");
    Button buttonSquare = new Button("x\u00B2");
    Button buttonReciprocal = new Button("1/x");
    Button buttonSqrt = new Button("\u221A");

    
    //Creating Constructor of the Class
    AwtCalculator(){

        prepareFrame();
        addComponents();
        addActionEvent();
        

    }
    
     public void prepareFrame(){

         //Setting Frame's Property
        frame.setSize(300,490);
        frame.setLayout(null);
        frame.setBackground(new Color(12,12,93));
        frame.setResizable(false);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
        frame.addWindowListener(
                new WindowAdapter(){
                    public void windowClosing(WindowEvent e) { System.exit(0); }
                }
        );
    }
     
      public void addComponents(){

          //Setting properties of the Components and adding them to the Frame
        label.setBounds(10, 40, 200, 20);
        label.setForeground(Color.white);
        label.setFont(new Font("Arial",Font.BOLD,15));
        frame.add(label);

        textField.setBounds(15,60,270,35);
        textField.setFont(new Font("Arial",Font.BOLD,20));
        textField.setEditable(false);
        frame.add(textField);


        onCheckbox.setBounds(15, 100, 60, 40);
        onCheckbox.setFont(new Font("Arial", Font.BOLD, 14));
        onCheckbox.setBackground(new Color(12,12,93));
        onCheckbox.setForeground(Color.white);
        onCheckbox.setFocusable(false);
        frame.add(onCheckbox);

        offCheckbox.setBounds(15, 125, 60, 40);
        offCheckbox.setFont(new Font("Arial", Font.BOLD, 14));
        offCheckbox.setBackground(new Color(12,12,93));
        offCheckbox.setForeground(Color.white);
        offCheckbox.setFocusable(false);
        frame.add(offCheckbox);

        buttonSeven.setBounds(15, 230, 60, 40);
        buttonSeven.setFont(new Font("Arial", Font.BOLD, 20));
        buttonSeven.setFocusable(false);
        frame.add(buttonSeven);

        buttonEight.setBounds(85, 230, 60, 40);
        buttonEight.setFont(new Font("Arial", Font.BOLD, 20));
        buttonEight.setFocusable(false);
        frame.add(buttonEight);

        buttonNine.setBounds(155, 230, 60, 40);
        buttonNine.setFont(new Font("Arial", Font.BOLD, 20));
        buttonNine.setFocusable(false);
        frame.add(buttonNine);

        buttonFour.setBounds(15, 290, 60, 40);
        buttonFour.setFont(new Font("Arial", Font.BOLD, 20));
        buttonFour.setFocusable(false);
        frame.add(buttonFour);

        buttonFive.setBounds(85, 290, 60, 40);
        buttonFive.setFont(new Font("Arial", Font.BOLD, 20));
        buttonFive.setFocusable(false);
        frame.add(buttonFive);

        buttonSix.setBounds(155, 290, 60, 40);
        buttonSix.setFont(new Font("Arial", Font.BOLD, 20));
        buttonSix.setFocusable(false);
        frame.add(buttonSix);

        buttonOne.setBounds(15, 350, 60, 40);
        buttonOne.setFont(new Font("Arial", Font.BOLD, 20));
        buttonOne.setFocusable(false);
        frame.add(buttonOne);

        buttonTwo.setBounds(85, 350, 60, 40);
        buttonTwo.setFont(new Font("Arial", Font.BOLD, 20));
        buttonTwo.setFocusable(false);
        frame.add(buttonTwo);

        buttonThree.setBounds(155, 350, 60, 40);
        buttonThree.setFont(new Font("Arial", Font.BOLD, 20));
        buttonThree.setFocusable(false);
        frame.add(buttonThree);

        buttonDot.setBounds(155, 410, 60, 40);
        buttonDot.setFont(new Font("Arial", Font.BOLD, 20));
        buttonDot.setFocusable(false);
        frame.add(buttonDot);

        buttonZero.setBounds(15, 410, 60, 40);
        buttonZero.setFont(new Font("Arial", Font.BOLD, 20));
        buttonZero.setFocusable(false);
        frame.add(buttonZero);

        buttonNegative.setBounds(85,410,60,40);
        buttonNegative.setFont(new Font("Arial",Font.BOLD,20));
        buttonNegative.setFocusable(false);
        frame.add(buttonNegative);

        buttonEqual.setBounds(225, 350, 60, 100);
        buttonEqual.setFont(new Font("Arial", Font.BOLD, 20));
        buttonEqual.setBackground(new Color(72, 231, 172));
        buttonEqual.setFocusable(false);
        frame.add(buttonEqual);

        buttonDiv.setBounds(225, 110, 60, 40);
        buttonDiv.setFont(new Font("Arial", Font.BOLD, 20));
        buttonDiv.setBackground(new Color(72, 231, 172));
        buttonDiv.setFocusable(false);
        frame.add(buttonDiv);

        buttonSqrt.setBounds(15, 170, 60, 40);
        buttonSqrt.setFont(new Font("Arial", Font.BOLD, 18));
        buttonSqrt.setFocusable(false);
        frame.add(buttonSqrt);

        buttonMul.setBounds(225, 230, 60, 40);
        buttonMul.setFont(new Font("Arial", Font.BOLD, 20));
        buttonMul.setBackground(new Color(72, 231, 172));
        buttonMul.setFocusable(false);
        frame.add(buttonMul);

        buttonMinus.setBounds(225, 170, 60, 40);
        buttonMinus.setFont(new Font("Arial", Font.BOLD, 20));
        buttonMinus.setBackground(new Color(72, 231, 172));
        buttonMinus.setFocusable(false);
        frame.add(buttonMinus);

        buttonPlus.setBounds(225, 290, 60, 40);
        buttonPlus.setFont(new Font("Arial", Font.BOLD, 20));
        buttonPlus.setBackground(new Color(72, 231, 172));
        buttonPlus.setFocusable(false);
        frame.add(buttonPlus);

        buttonSquare.setBounds(85, 170, 60, 40);
        buttonSquare.setFont(new Font("Arial", Font.BOLD, 20));
        buttonSquare.setFocusable(false);
        frame.add(buttonSquare);

        buttonReciprocal.setBounds(155, 170, 60, 40);
        buttonReciprocal.setFont(new Font("Arial", Font.BOLD, 15));
        buttonReciprocal.setFocusable(false);
        frame.add(buttonReciprocal);

        buttonDelete.setBounds(155, 110, 60, 40);
        buttonDelete.setFont(new Font("Arial", Font.BOLD, 12));
        buttonDelete.setBackground(Color.red);
        buttonDelete.setForeground(Color.white);
        buttonDelete.setFocusable(false);
        frame.add(buttonDelete);

        buttonClear.setBounds(85, 110, 60, 40);
        buttonClear.setFont(new Font("Arial", Font.BOLD, 12));
        buttonClear.setBackground(Color.red);
        buttonClear.setForeground(Color.white);
        buttonClear.setFocusable(false);
        frame.add(buttonClear);



    }
      
       public void addActionEvent(){
           
           //Registering ActionListener and ItemListener
        onCheckbox.addItemListener(this);
        offCheckbox.addItemListener(this);
        buttonClear.addActionListener(this);
        buttonDelete.addActionListener(this);
        buttonDiv.addActionListener(this);
        buttonSqrt.addActionListener(this);
        buttonSquare.addActionListener(this);
        buttonReciprocal.addActionListener(this);
        buttonMinus.addActionListener(this);
        buttonSeven.addActionListener(this);
        buttonEight.addActionListener(this);
        buttonNine.addActionListener(this);
        buttonMul.addActionListener(this);
        buttonFour.addActionListener(this);
        buttonFive.addActionListener(this);
        buttonSix.addActionListener(this);
        buttonPlus.addActionListener(this);
        buttonOne.addActionListener(this);
        buttonTwo.addActionListener(this);
        buttonThree.addActionListener(this);
        buttonEqual.addActionListener(this);
        buttonZero.addActionListener(this);
        buttonDot.addActionListener(this);
        buttonNegative.addActionListener(this);
    }
    public static void main(String[] args) {
       
        //Creating object of the AwtCalculator class which will call the constructor
        AwtCalculator calculator = new AwtCalculator();
    }

    //Overriding actionPerformed() method
    @Override
    public void actionPerformed(ActionEvent e) {
        Object source = e.getSource();
        if (source == buttonClear) {
            textField.setText("");
        }else if(source==buttonDelete){
            int length = textField.getText().length();
            int number = length - 1;


            if (length > 0) {
                StringBuilder back = new StringBuilder(textField.getText());
                back.deleteCharAt(number);
                textField.setText(back.toString());

            }if (textField.getText().endsWith("")) {
                label.setText("");
            }
        }

       else if(source==buttonZero){
           if(textField.getText().equals("0")) {
                return;
            }
            else {
                textField.setText(textField.getText() + "0");
            }
        } else if (source == buttonOne) {
            textField.setText(textField.getText() + "1");
        } else if (source == buttonTwo) {
            textField.setText(textField.getText() + "2");
        } else if (source == buttonThree) {
            textField.setText(textField.getText() + "3");
        } else if (source == buttonFour) {
            textField.setText(textField.getText() + "4");
        } else if (source == buttonFive) {
            textField.setText(textField.getText() + "5");
        } else if (source == buttonSix) {
            textField.setText(textField.getText() + "6");
        } else if (source == buttonSeven) {
            textField.setText(textField.getText() + "7");
        } else if (source == buttonEight) {
            textField.setText(textField.getText() + "8");
        } else if (source == buttonNine) {
            textField.setText(textField.getText() + "9");
        } else if (source == buttonDot) {
            if (textField.getText().contains(".")) {
                return;
            } else {
                textField.setText(textField.getText() + ".");
            }
        }else if(source==buttonPlus){
           String str = textField.getText();
            num1=Double.parseDouble(textField.getText());
            calculation=1;
            textField.setText("");
            label.setText(str + "+");
        }else if(source==buttonMinus){
            String str = textField.getText();
            num1=Double.parseDouble(textField.getText());
            calculation=2;
            textField.setText("");
            label.setText(str + "-");
        }else if(source==buttonMul){
            String str = textField.getText();
            num1=Double.parseDouble(textField.getText());
            calculation=3;
            textField.setText("");
            label.setText(str + "X");
        }else if(source==buttonDiv){
            String str = textField.getText();
            num1=Double.parseDouble(textField.getText());
            calculation=4;
            textField.setText("");
            label.setText(str + "/");
        }else if (source == buttonSqrt) {
            String str = textField.getText();
            num1 = Double.parseDouble(textField.getText());
            Double sqrt = Math.sqrt(num1);
            textField.setText(Double.toString(sqrt));

        } else if (source == buttonSquare) {
            String str = textField.getText();
            num1 = Double.parseDouble(textField.getText());
            double square = Math.pow(num1, 2);
            String string = Double.toString(square);
            if (string.endsWith(".0")) {
                textField.setText(string.replace(".0", ""));
            } else {
                textField.setText(string);
            }
        } else if (source == buttonReciprocal) {
            num1 = Double.parseDouble(textField.getText());
            double reciprocal = 1 / num1;
            String string = Double.toString(reciprocal);
            if (string.endsWith(".0")) {
                textField.setText(string.replace(".0", ""));
            } else {
                textField.setText(string);
            }
        }else if(source==buttonNegative){
            if(textField.getText().equals("")) {
                return;
            }
           double temp = Double.parseDouble(textField.getText());
           temp = temp * (-1);
           textField.setText(String.valueOf(temp));
        }
       else if(source==buttonEqual){
           //Setting functionalities for equals button 
            num2=Double.parseDouble(textField.getText());
            switch(calculation){
                case 1:
                    result=num1+num2;
                    break;
                case 2:
                    result=num1-num2;
                    break;
                case 3:
                    result=num1*num2;
                    break;
                case 4:
                    result=num1/num2;
                    break;
            }
            if (Double.toString(result).endsWith(".0")) {
                textField.setText(Double.toString(result).replace(".0", ""));
            } else {
                textField.setText(Double.toString(result));
            }
            label.setText("");
            num1=result;

        }
        
    }

    //Overriding itemStateChanged() method
    @Override
    public void itemStateChanged(ItemEvent e) {
        
        //Setting functionalities for on and off button
        if(e.getSource()==onCheckbox){
            enable();
        }
        else if(e.getSource()==offCheckbox){
            disable();
        }
         
    }
    
     public void enable(){

        onCheckbox.setEnabled(false);
        offCheckbox.setEnabled(true);
        textField.setEnabled(true);
        label.setEnabled(true);
        buttonClear.setEnabled(true);
        buttonDelete.setEnabled(true);
        buttonDiv.setEnabled(true);
        buttonSqrt.setEnabled(true);
        buttonSquare.setEnabled(true);
        buttonReciprocal.setEnabled(true);
        buttonMinus.setEnabled(true);
        buttonSeven.setEnabled(true);
        buttonEight.setEnabled(true);
        buttonNine.setEnabled(true);
        buttonMul.setEnabled(true);
        buttonFour.setEnabled(true);
        buttonFive.setEnabled(true);
        buttonSix.setEnabled(true);
        buttonPlus.setEnabled(true);
        buttonOne.setEnabled(true);
        buttonTwo.setEnabled(true);
        buttonThree.setEnabled(true);
        buttonEqual.setEnabled(true);
        buttonZero.setEnabled(true);
        buttonDot.setEnabled(true);
        buttonNegative.setEnabled(true);
    }
    public void disable(){

        onCheckbox.setEnabled(true);
        offCheckbox.setEnabled(false);
        label.setText("");
        textField.setText("");
        buttonClear.setEnabled(false);
        buttonDelete.setEnabled(false);
        buttonDiv.setEnabled(false);
        buttonSqrt.setEnabled(false);
        buttonSquare.setEnabled(false);
        buttonReciprocal.setEnabled(false);
        buttonMinus.setEnabled(false);
        buttonSeven.setEnabled(false);
        buttonEight.setEnabled(false);
        buttonNine.setEnabled(false);
        buttonMul.setEnabled(false);
        buttonFour.setEnabled(false);
        buttonFive.setEnabled(false);
        buttonSix.setEnabled(false);
        buttonPlus.setEnabled(false);
        buttonOne.setEnabled(false);
        buttonTwo.setEnabled(false);
        buttonThree.setEnabled(false);
        buttonEqual.setEnabled(false);
        buttonZero.setEnabled(false);
        buttonDot.setEnabled(false);
        buttonNegative.setEnabled(false);
    }
    
}

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package awtcalculator;

//importing all necessary packages

import java.awt.*;

import java.awt.event.*;

public class AwtCalculator implements ActionListener, ItemListener {

//Declaring and Initializing variable for calculations

double num1=0, num2=0, result=0;

int calculation;

//Creating object of Frame Class

Frame frame=new Frame("Calculator");

//Creating objects of all the components

Label label=new Label();

TextField textField=new TextField();

CheckboxGroup checkboxGroup=new CheckboxGroup();

Checkbox onCheckbox=new Checkbox("On",checkboxGroup,true);

Checkbox offCheckbox=new Checkbox("Off",checkboxGroup,false);

Button buttonZero = new Button("0");

Button buttonOne = new Button("1");

Button buttonTwo = new Button("2");

Button buttonThree = new Button("3");

Button buttonFour = new Button("4");

Button buttonFive = new Button("5");

Button buttonSix = new Button("6");

Button buttonSeven = new Button("7");

Button buttonEight = new Button("8");

Button buttonNine = new Button("9");

Button buttonDot = new Button(".");

Button buttonClear = new Button("CLR");

Button buttonDelete = new Button("DEL");

Button buttonEqual = new Button("=");

Button buttonNegative = new Button("(-)");

Button buttonMul = new Button("x");

Button buttonDiv = new Button("/");

Button buttonPlus = new Button("+");

Button buttonMinus = new Button("-");

Button buttonSquare = new Button("x\u00B2");

Button buttonReciprocal = new Button("1/x");

Button buttonSqrt = new Button("\u221A");

//Creating Constructor of the Class

AwtCalculator(){

prepareFrame();

addComponents();

addActionEvent();

}

public void prepareFrame(){

//Setting Frame's Property

frame.setSize(300,490);

frame.setLayout(null);

frame.setBackground(new Color(12,12,93));

frame.setResizable(false);

frame.setLocationRelativeTo(null);

frame.setVisible(true);

frame.addWindowListener(

new WindowAdapter(){

public void windowClosing(WindowEvent e) { System.exit(0); }

}

);

}

public void addComponents(){

//Setting properties of the Components and adding them to the Frame

label.setBounds(10, 40, 200, 20);

label.setForeground(Color.white);

label.setFont(new Font("Arial",Font.BOLD,15));

frame.add(label);

textField.setBounds(15,60,270,35);

textField.setFont(new Font("Arial",Font.BOLD,20));

textField.setEditable(false);

frame.add(textField);

onCheckbox.setBounds(15, 100, 60, 40);

onCheckbox.setFont(new Font("Arial", Font.BOLD, 14));

onCheckbox.setBackground(new Color(12,12,93));

onCheckbox.setForeground(Color.white);

onCheckbox.setFocusable(false);

frame.add(onCheckbox);

offCheckbox.setBounds(15, 125, 60, 40);

offCheckbox.setFont(new Font("Arial", Font.BOLD, 14));

offCheckbox.setBackground(new Color(12,12,93));

offCheckbox.setForeground(Color.white);

offCheckbox.setFocusable(false);

frame.add(offCheckbox);

buttonSeven.setBounds(15, 230, 60, 40);

buttonSeven.setFont(new Font("Arial", Font.BOLD, 20));

buttonSeven.setFocusable(false);

frame.add(buttonSeven);

buttonEight.setBounds(85, 230, 60, 40);

buttonEight.setFont(new Font("Arial", Font.BOLD, 20));

buttonEight.setFocusable(false);

frame.add(buttonEight);

buttonNine.setBounds(155, 230, 60, 40);

buttonNine.setFont(new Font("Arial", Font.BOLD, 20));

buttonNine.setFocusable(false);

frame.add(buttonNine);

buttonFour.setBounds(15, 290, 60, 40);

buttonFour.setFont(new Font("Arial", Font.BOLD, 20));

buttonFour.setFocusable(false);

frame.add(buttonFour);

buttonFive.setBounds(85, 290, 60, 40);

buttonFive.setFont(new Font("Arial", Font.BOLD, 20));

buttonFive.setFocusable(false);

frame.add(buttonFive);

buttonSix.setBounds(155, 290, 60, 40);

buttonSix.setFont(new Font("Arial", Font.BOLD, 20));

buttonSix.setFocusable(false);

frame.add(buttonSix);

buttonOne.setBounds(15, 350, 60, 40);

buttonOne.setFont(new Font("Arial", Font.BOLD, 20));

buttonOne.setFocusable(false);

frame.add(buttonOne);

buttonTwo.setBounds(85, 350, 60, 40);

buttonTwo.setFont(new Font("Arial", Font.BOLD, 20));

buttonTwo.setFocusable(false);

frame.add(buttonTwo);

buttonThree.setBounds(155, 350, 60, 40);

buttonThree.setFont(new Font("Arial", Font.BOLD, 20));

buttonThree.setFocusable(false);

frame.add(buttonThree);

buttonDot.setBounds(155, 410, 60, 40);

buttonDot.setFont(new Font("Arial", Font.BOLD, 20));

buttonDot.setFocusable(false);

frame.add(buttonDot);

buttonZero.setBounds(15, 410, 60, 40);

buttonZero.setFont(new Font("Arial", Font.BOLD, 20));

buttonZero.setFocusable(false);

frame.add(buttonZero);

buttonNegative.setBounds(85,410,60,40);

buttonNegative.setFont(new Font("Arial",Font.BOLD,20));

buttonNegative.setFocusable(false);

frame.add(buttonNegative);

buttonEqual.setBounds(225, 350, 60, 100);

buttonEqual.setFont(new Font("Arial", Font.BOLD, 20));

buttonEqual.setBackground(new Color(72, 231, 172));

buttonEqual.setFocusable(false);

frame.add(buttonEqual);

buttonDiv.setBounds(225, 110, 60, 40);

buttonDiv.setFont(new Font("Arial", Font.BOLD, 20));

buttonDiv.setBackground(new Color(72, 231, 172));

buttonDiv.setFocusable(false);

frame.add(buttonDiv);

buttonSqrt.setBounds(15, 170, 60, 40);

buttonSqrt.setFont(new Font("Arial", Font.BOLD, 18));

buttonSqrt.setFocusable(false);

frame.add(buttonSqrt);

buttonMul.setBounds(225, 230, 60, 40);

buttonMul.setFont(new Font("Arial", Font.BOLD, 20));

buttonMul.setBackground(new Color(72, 231, 172));

buttonMul.setFocusable(false);

frame.add(buttonMul);

buttonMinus.setBounds(225, 170, 60, 40);

buttonMinus.setFont(new Font("Arial", Font.BOLD, 20));

buttonMinus.setBackground(new Color(72, 231, 172));

buttonMinus.setFocusable(false);

frame.add(buttonMinus);

buttonPlus.setBounds(225, 290, 60, 40);

buttonPlus.setFont(new Font("Arial", Font.BOLD, 20));

buttonPlus.setBackground(new Color(72, 231, 172));

buttonPlus.setFocusable(false);

frame.add(buttonPlus);

buttonSquare.setBounds(85, 170, 60, 40);

buttonSquare.setFont(new Font("Arial", Font.BOLD, 20));

buttonSquare.setFocusable(false);

frame.add(buttonSquare);

buttonReciprocal.setBounds(155, 170, 60, 40);

buttonReciprocal.setFont(new Font("Arial", Font.BOLD, 15));

buttonReciprocal.setFocusable(false);

frame.add(buttonReciprocal);

buttonDelete.setBounds(155, 110, 60, 40);

buttonDelete.setFont(new Font("Arial", Font.BOLD, 12));

buttonDelete.setBackground(Color.red);

buttonDelete.setForeground(Color.white);

buttonDelete.setFocusable(false);

frame.add(buttonDelete);

buttonClear.setBounds(85, 110, 60, 40);

buttonClear.setFont(new Font("Arial", Font.BOLD, 12));

buttonClear.setBackground(Color.red);

buttonClear.setForeground(Color.white);

buttonClear.setFocusable(false);

frame.add(buttonClear);

}

public void addActionEvent(){

//Registering ActionListener and ItemListener

onCheckbox.addItemListener(this);

offCheckbox.addItemListener(this);

buttonClear.addActionListener(this);

buttonDelete.addActionListener(this);

buttonDiv.addActionListener(this);

buttonSqrt.addActionListener(this);

buttonSquare.addActionListener(this);

buttonReciprocal.addActionListener(this);

buttonMinus.addActionListener(this);

buttonSeven.addActionListener(this);

buttonEight.addActionListener(this);

buttonNine.addActionListener(this);

buttonMul.addActionListener(this);

buttonFour.addActionListener(this);

buttonFive.addActionListener(this);

buttonSix.addActionListener(this);

buttonPlus.addActionListener(this);

buttonOne.addActionListener(this);

buttonTwo.addActionListener(this);

buttonThree.addActionListener(this);

buttonEqual.addActionListener(this);

buttonZero.addActionListener(this);

buttonDot.addActionListener(this);

buttonNegative.addActionListener(this);

}

public static void main(String[] args) {

//Creating object of the AwtCalculator class which will call the constructor

AwtCalculator calculator = new AwtCalculator();

}

//Overriding actionPerformed() method

@Override

public void actionPerformed(ActionEvent e) {

Object source = e.getSource();

if (source == buttonClear) {

textField.setText("");

}else if(source==buttonDelete){

int length = textField.getText().length();

int number = length - 1;

if (length > 0) {

StringBuilder back = new StringBuilder(textField.getText());

back.deleteCharAt(number);

textField.setText(back.toString());

}if (textField.getText().endsWith("")) {

label.setText("");

}

else if(source==buttonZero){

if(textField.getText().equals("0")) {

return;

}

else {

textField.setText(textField.getText() + "0");

}

} else if (source == buttonOne) {

textField.setText(textField.getText() + "1");

} else if (source == buttonTwo) {

textField.setText(textField.getText() + "2");

} else if (source == buttonThree) {

textField.setText(textField.getText() + "3");

} else if (source == buttonFour) {

textField.setText(textField.getText() + "4");

} else if (source == buttonFive) {

textField.setText(textField.getText() + "5");

} else if (source == buttonSix) {

textField.setText(textField.getText() + "6");

} else if (source == buttonSeven) {

textField.setText(textField.getText() + "7");

} else if (source == buttonEight) {

textField.setText(textField.getText() + "8");

} else if (source == buttonNine) {

textField.setText(textField.getText() + "9");

} else if (source == buttonDot) {

if (textField.getText().contains(".")) {

return;

} else {

textField.setText(textField.getText() + ".");

}

}else if(source==buttonPlus){