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Explain the concepts and capabilities of Aspect-Oriented Programming, AOP.- Aspect-Oriented Programming (AOP) complements OO programming.
- It allows the developer to dynamically modify the static OO model to create a system that can grow to meet new requirements.
- An application can adopt new characteristics as it develops just as objects in the real world can change their states during their lifecycles.
Terminology
- Cross-cutting concerns: Although most classes in an OO model will perform a single, specific function, they share secondary requirements with other classes. Although the primary functionality of each class is very different, the code needed to perform the secondary functionality is often identical.
- Advice: This is the additional code that you want to apply to your existing model.
- Point-cut: This is the term given to the point of execution in the application at which cross-cutting concern needs to be applied.
- Aspect: The combination of the point-cut and the advice is termed an aspect.Explain the concepts and capabilities of Aspect-Oriented Programming, AOP.AOP concepts:
- Aspect: A cross cutting modularization across multiple objects. Aspects are implemented by using regular classes.
- Join point: A point while executing a program, such as running an exception or a program. In certain frameworks , a method is always treated as a join point.
- Advice: Advice is an action that is taken by an aspect at a certain joint point. “around”,”before”,”after” are different types of advice.
- Pointcut: A condition / predicate that matches join points. An advice is associated with a point cut expression. It is run at any joint point matched by the point cut.
- Target object: An object that is advised by one or more aspects.
- AOP proxy: To implement the aspect contracts or advice methods, AOP proxy object is created.
- Weaving: Applications or objects are linked by aspects by weaving process, for creation of an advised object. This process can be performed at runtime.
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