calculator-java

A simple Java CLI calculator with JUnit tests, Makefile automation, Docker support, and GitHub Actions CI/CD pipeline.

Features

• Basic arithmetic operations: add, sub, mul, div
• JUnit 4-based unit testing
• Build automation using Makefile
• Dockerized CLI app
• GitHub Actions CI/CD workflow for:
  • Automated builds and test runs
  • Docker image builds
  • Release tagging and artifacts

Makefile Targets

• make build — Compile all sources
• make test — Run unit tests
• make run — Run the calculator CLI
• make clean — Clean build and release folders
• make release — Create release artifact and tag
• make all — Build and test

Dependencies

• Put JUnit JARs in a lib/ folder (download from JUnit site):

calculator-java/
└── lib/
    ├── junit-4.13.2.jar
    └── hamcrest-core-1.3.jar

Project Structure

calculator-java/
├── src/
│   ├── Calculator.java        # Core calculator logic
│   └── Main.java              # CLI entry point
│
├── test/
│   └── CalculatorTest.java    # JUnit test cases
│
├── lib/
│   ├── junit-4.13.2.jar       # (Downloaded by CI or added manually)
│   └── hamcrest-core-1.3.jar
│
├── build/                     # Compiled .class files (generated)
│
├── release/                   # Tagged releases (generated)
│
├── .github/
│   └── workflows/
│       └── ci.yml             # GitHub Actions workflow for CI/CD
│
├── Dockerfile                 # Docker image definition
├── .dockerignore             # Ignore build/release dirs in Docker context
├── Makefile                   # Commands: build, test, run, clean, release
├── .release-tag               # Simple version tracking file
├── README.md                  # Project description, usage, and instructions

Docker

To run manually:

docker build -t java-calculator .
docker run -it java-calculator