Today we delved into the world of Binary Search Trees, implementing a robust BST data structure while strengthening our testing practices.

The code changes from this session can be found here.

Day 10 Summary

Overview

Implemented a comprehensive Binary Search Tree data structure with proper testing methodology, covering core tree operations and utility methods.

Environment & Tools

  • JUnit 5 for testing framework
  • Proper test organization with @DisplayName annotations
  • Clean separation of test and implementation code

Concepts Covered

Binary Search Tree Implementation

  • Generic type support with Comparable constraint
  • Core BST properties and invariants
  • Node structure and relationships
  • Recursive tree operations

Tree Operations

  • Insertion maintaining BST property
  • Deletion handling all cases (leaf, one child, two children)
  • Three types of traversals (in-order, pre-order, post-order)
  • Search/contains operation

Utility Methods

  • Size calculation
  • Tree height computation
  • Min/max value finding
  • BST property validation

Testing Practices

  • Clean test organization
  • Descriptive test naming
  • Test isolation with @BeforeEach
  • Edge case coverage

Implementation Progress

  • Created complete BST implementation
  • Added comprehensive traversal methods
  • Implemented utility operations
  • Established proper test suite

Key Takeaways

  • BST provides efficient searching and ordering
  • Recursive solutions for tree operations
  • Importance of maintaining BST invariants
  • Value of proper test organization
  • Benefits of descriptive test naming

Next Steps

Ready to explore:

  • Tree balancing techniques
  • AVL and Red-Black trees
  • Additional tree operations
  • Performance analysis

Master’s Reflection

The apprentice demonstrated strong understanding of both data structure implementation and testing practices. The transition from ad-hoc testing to proper JUnit organization shows growing maturity in development practices. The methodical approach to implementing BST operations and attention to edge cases suggests a solid foundation for exploring more complex tree structures in future sessions.