A simple desktop calculator built in Java with Swing, supporting the four basic arithmetic operations through an interactive graphical interface.
Single-window application that takes two numeric inputs and performs addition, subtraction, multiplication or division based on the user's selection. Includes input validation, error handling for invalid numbers, and a guard against division by zero.
- Two input fields for the operands and one read-only field for the result
- Four operation buttons: Add, Subtract, Multiply, Divide
- Clear button to reset all fields
- Exit button to close the application
- Division-by-zero protection with a user-facing error dialog
- Input validation — non-numeric values trigger an error message instead of crashing
| Aspect | Implementation |
|---|---|
| Framework | Java Swing (JFrame, JTextField, JButton, JLabel, JOptionPane) |
| Layout | FlowLayout for simple, predictable component arrangement |
| Event Handling | Implements ActionListener to dispatch button events |
| Threading | Uses SwingUtilities.invokeLater to ensure the GUI runs on the Event Dispatch Thread |
| Error Handling | try/catch on NumberFormatException plus an explicit zero-division check |
- Make sure you have Java JDK installed (version 8 or higher)
- Compile the source file:
javac Calculation.java- Run the application:
java Calculation- Building event-driven Java GUIs with Swing
- Handling user input safely with exception-based validation
- Ensuring the UI thread runs properly via the Event Dispatch Thread
- Designing clean user feedback with dialog boxes for error states
Part of my IT learning journey at the Academy of Interactive Technology (AIT) — see more at github.com/Lmg15186