Reflection
Reflection is a programming language feature that enables a program to inspect and modify its own structure and behavior at runtime. It allows code to examine classes, interfaces, fields, and methods, and to dynamically invoke methods or instantiate objects, often used for tasks like serialization, dependency injection, and debugging tools. This capability is typically available in languages like Java, C#, and Python, providing flexibility but with performance trade-offs.
Developers should learn reflection when building frameworks, libraries, or applications that require dynamic behavior, such as creating generic data mappers, implementing plugin systems, or developing testing tools that need to access private members. It is essential for scenarios where the code structure is not known at compile time, enabling advanced metaprogramming and reducing boilerplate code in complex systems.