Code Refactoring Best Practices

Study Notes

Definition: Restructuring existing code without changing its external behavior to improve internal structure, readability, and maintainability.
Importance:
- Improves code quality and readability
- Reduces bugs and errors
- Enhances performance
- Simplifies code maintenance and updates
Best practices:
- Refactor in small, incremental steps
- Use automated testing to ensure functional correctness
- Focus on one improvement at a time
- Consider the entire system, not just isolated components

Importance:
- Ensures robustness and reliability of Java applications
- Provides informative error messages for users and developers
- Helps prevent data corruption and loss
Best practices:
- Use try-catch blocks to handle exceptions
- Catch specific exceptions rather than general exceptions
- Log errors and exceptions for debugging and analysis
- Use finally blocks for resource cleanup and release
- Avoid catching RuntimeException and its subclasses
- Document error handling mechanisms and strategies

Definition: Reusable solutions to common software design problems
Importance:
- Improves code maintainability, flexibility, and scalability
- Enhances code readability and understandability
- Facilitates communication among developers
Key patterns:
- Creational patterns (e.g., Singleton, Factory)
- Structural patterns (e.g., Adapter, Composite)
- Behavioral patterns (e.g., Observer, Strategy)
Best practices:
- Use design patterns to solve specific problems, not as a general approach
- Understand the problem and the pattern before applying it
- Keep patterns simple and focused on a specific problem
- Document pattern usage and rationale

Importance:
- Enhances application responsiveness and user experience
- Reduces resource utilization and costs
- Improves system scalability and reliability
Best practices:
- Identify performance bottlenecks using profiling tools
- Optimize algorithms and data structures
- Minimize object creation and garbage collection
- Use caching and lazy loading when applicable
- Optimize database queries and connections
- Consider parallel processing and concurrency
- Monitor and analyze performance metrics

Code refactoring involves restructuring existing code to improve its internal structure, readability, and maintainability without changing its external behavior.
Refactoring improves code quality, reduces bugs and errors, enhances performance, and simplifies code maintenance and updates.
To refactor effectively, make small, incremental changes, use automated testing to ensure functional correctness, focus on one improvement at a time, and consider the entire system.

Proper error handling ensures robustness and reliability of Java applications, provides informative error messages, and helps prevent data corruption and loss.
Use try-catch blocks to handle exceptions, catch specific exceptions, and log errors and exceptions for debugging and analysis.
Avoid catching RuntimeException and its subclasses, and document error handling mechanisms and strategies.

Design patterns are reusable solutions to common software design problems, improving code maintainability, flexibility, and scalability.
Creational patterns (e.g., Singleton, Factory), structural patterns (e.g., Adapter, Composite), and behavioral patterns (e.g., Observer, Strategy) are key design patterns.
Use design patterns to solve specific problems, understand the problem and the pattern before applying it, and keep patterns simple and focused on a specific problem.

Performance optimization is crucial for enhancing application responsiveness, reducing resource utilization, and improving system scalability and reliability.
Identify performance bottlenecks using profiling tools, optimize algorithms and data structures, minimize object creation and garbage collection, and use caching and lazy loading when applicable.
Optimize database queries and connections, consider parallel processing and concurrency, and monitor and analyze performance metrics.