TDD (Test-Driven Development) is an essential approach to Serverless Java development that emphasizes writing tests before writing the actual code.
Importance of TDD in Serverless Java Development:
- Better Code Quality: Ensures functionality, early bug detection
- Faster Feedback Loop: Immediate insights, faster development
- Easier Refactoring: Confident changes, comprehensive tests
- Design Improvement: Thoughtful solutions, better planning
- Maintainability: Easy to maintain, living documentation
- Regression Testing: Existing functionality remains intact
- Collaboration: Common language, enhanced teamwork
- Confidence in Deployment: Robustness for smooth deployment
- Cost-Effectiveness: Saves time and money, fewer bugs
- CI/CD Integration: Fits automated pipelines, maintain quality
Let us start with the required Tools to the setup environment:
AWS Free Account
Lambda functions in Java
JUnit5: This is a popular framework for unit testing Java code.
Mockito: This is a popular framework for mocking objects in unit tests.
Build: Maven
TDD with mocks:
Your Code Objects vs Others Code Objects
Mocks in unit tests to simulate the behavior of other objects.
Continuous integration (CI) to automate the testing of your Java code.
Writing Functional and Unit Tests:
Unit testing: Isolates your code from dependencies. So as to test the business logic only. They are faster.
Integration testing: Interaction with dependencies is tested end to end.
Refactoring:
Refactor Java code to improve its design and readability.
Test coverage:
Test coverage: Increased confidence in the code; Reduced risk of regressions. Improved code quality.
Types of test coverage:
Different types of test coverage to measure the code quality.
Improve test coverage:
Write more unit tests and use code coverage tools.
Test coverage Thresholds:
The minimum percentage of code that must be covered by tests in order for a build to pass: 80%
Identifying potential bugs early in the development process.