Summary

Adds a new implementation demonstrating the Memento pattern with bounded undo/redo functionality. This example shows how to capture and restore object state while maintaining encapsulation.

The implementation includes:

• Originator class CatalogQueryState that creates and restores snapshots
• Nested Memento class QuerySnapshot with package-private access for encapsulation
• Caretaker class CatalogQueryHistory managing bounded undo/redo stacks (max 20 items)
• Support for complex state including search text, filters, and sort configuration
• Complete working example with MainApp demonstrating undo/redo operations
• Deep copying mechanism to prevent state corruption

Technical Details

• Location: section-04-behavioral-design-patterns/13-memento/
• Language: Java 24
• Build tool: Maven
• Pattern roles: Originator, Memento (nested), Caretaker, Client
• Key features: Bounded history, deep copying, redo-clearing on new changes

Test Plan

• Build verification: Maven compilation successful
• Code follows existing repository patterns and conventions
• JavaDoc comments present for all classes
• Demonstrates proper encapsulation with nested Memento class
• No compilation errors or warnings (excluding JDK version warnings)