Introduction
White Box Testing is an advanced testing technique where testers analyze the internal code structure of an application. Unlike black box testing, this method requires programming knowledge.
What is White Box Testing?
White Box Testing is a testing method where the internal logic, code structure, and implementation of the system are tested. It focuses on verifying code flow, conditions, loops, and internal logic.
Testers examine how the system processes input and produces output at the code level.
Key Characteristics of White Box Testing
- Requires programming knowledge
- Tests internal code structure
- Verifies logic paths and conditions
- Performed mostly by developers
White Box Testing Techniques
- Statement Coverage
- Branch Coverage
- Path Coverage
- Condition Coverage
- Loop Testing
Example: If code contains an "if-else" condition, both paths must be tested.
Types of White Box Testing
- Unit Testing
- Integration Testing
- Code Coverage Testing
Real-World Examples
Example 1: Login Function Code
- Check valid credentials condition
- Check invalid credentials condition
- Test error message return logic
Example 2: Loop Testing
- Test loop execution zero times
- Test loop execution once
- Test loop execution multiple times
Advantages of White Box Testing
- Thorough code-level validation
- Improves code quality
- Detects hidden logic errors
- Optimizes performance
Disadvantages of White Box Testing
- Requires programming skills
- Time-consuming for large systems
- May miss requirement-level defects
White Box Testing Interview Questions
What is white box testing?
White box testing verifies internal code logic and structure.
Who performs white box testing?
Usually developers or technical testers.
What is branch coverage?
Branch coverage ensures every possible branch in code is executed at least once.
Frequently Asked Questions
What is difference between white box and black box testing?
White box testing focuses on internal code, while black box testing focuses on functionality without seeing code.
Is white box testing part of unit testing?
Yes, unit testing often uses white box testing techniques.