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proxy pattern Proxy Pattern refers to providing a proxy for other objects to control access to this object. It belongs to structural pattern. In some cases, an object is inappropriate or cannot directly reference another object, and the proxy object can act as an intermediary between the client and the target object. The agent mode generally ...

Builder mode Meaning: generator mode is a creation mode, which enables you to create complex objects step by step. You can use the same creation code to generate objects of different types and forms. Looking at the picture, we can well understand that the picture is the assembly line mode in the factory. The builder is like the whole assemb ...

Finally to AOP, the front did not understand must follow the code to read more, otherwise this article is easy to get lost! If you don't say much, you can't change without its sect. First, the picture above. AOP sequence diagram Source code analysis 1. Initialization phase - > method of matching tangent points Go back to abstractautowi ...

Baidu definition: design mode (Design pattern) is a set of code design experience that is repeatedly used, known by most people, classified and catalogued. The purpose of using design patterns is to reuse code, make code easier to be understood by others and ensure code reliability. There is no doubt that design patterns win more for themselves ...

Basic introduction 1) One object should have minimal knowledge of other objects 2) The closer the relationship between classes, the greater the degree of coupling 3) The Demeter Principle is also called the least known principle, that is, the less a class knows about the class it depends on, the better. That is, no matter how complex the dep ...

1. Course objectives 1. Master the characteristics and application scenarios of decorator mode. 2. Master the fundamental difference between decorator mode and adapter mode. 3. Application and implementation principle of observer mode in source code. 4. Understand the advantages and disadvantages of decorator mode and observer mode. 2. ...

Usage scenario This is very important, because if you learn something and don't know what problem to solve, what's the use? The importance of understanding the usage scenario is much higher than whether you will implement this mode, because as long as you know what problems can be solved by using the builder mode, you can complete it after inve ...

Catalogue of series articles Design pattern - design principle Create mode - singleton mode (I) Creation mode - factory mode (II) Creation mode - prototype mode (III) Creative mode - builder mode (4) Structural mode - adapter mode (I) Structural mode - bridge mode (II) Structural mode - decorator mode (III) Structural mode - combined mode ...

In the book design patterns: the basis of reusable object-oriented software published by GoF, 23 design patterns are recorded. The essence of these design patterns is the understanding of encapsulation, inheritance and polymorphism of object-oriented design. There are 8 design patterns used in app development. Singleton mode Singleton pattern ...

The observer pattern defines a one to many dependency. When an object changes state, all its dependents will receive notification and update data. For example, we commonly set up monitoring, button Setonclicklistener is also a kind of observer. Core concerns The observer and the observed are loosely coupled. The observed only needs to know t ...