🧮 Java Swing Calculator (OnePlus Style)

A clean, professional Calculator Desktop Application built using pure Java (Swing).
This project is inspired by the OnePlus Nord Calculator UI and focuses on clean design, solid logic, and interview-ready code.

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🚀 Features

• Modern dark UI inspired by OnePlus Calculator
• Basic arithmetic operations:
  • Addition (+)
  • Subtraction (−)
  • Multiplication (×)
  • Division (÷)
• Extra calculator features:
  • AC (All Clear)
  • Backspace
  • Percentage (%)
  • Plus/Minus toggle (+/−)
  • Double Zero (00)
• Handles edge cases:
  • Division by zero
  • Clean integer / decimal output
• Keyboard-free, button-driven UI
• Fully event-driven using Java Swing

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🛠️ Tech Stack

• Language: Java
• GUI Framework: Java Swing
• IDE: IntelliJ IDEA
• Architecture: Single-class (simplified for learning & interviews)

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📸 UI Preview

Inspired by OnePlus Nord Calculator
Dark theme with orange operator buttons for clarity and usability

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🧠 Project Logic Overview

• Uses event-driven programming with ActionListener
• Maintains calculator state using:
  • firstNumber
  • operator
  • startNewNumber
• Clean separation of responsibilities using helper methods:
  • appendNumber()
  • setOperator()
  • calculate()
  • clearAll()
  • toggleSign()

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🧪 Edge Cases Handled

• Prevents multiple decimal points
• Shows Error on division by zero
• Automatically removes .0 from whole number results
• Resets calculator state correctly after each calculation

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▶️ How to Run

1. Clone the repository

   git clone https://github.com/your-username/java-swing-calculator.git

2.Open the project in IntelliJ IDEA

3.Run CalculatorFrame.java

4.Enjoy 🚀

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👨‍💻 Author

Abhishek Karande B.Tech IT | Java Developer | Swing GUI Projects

This project was built to strengthen core Java concepts and demonstrate clean desktop application development.

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⭐ If you like this project

Give it a ⭐ on GitHub — it really helps!