The interface segregation principle (Interface Segregation Principle, ISP) defines that the client should not rely on interfaces it does not need, and the dependency between classes should be established on the smallest interface. Simply put, it is to establish a single interface, not to create a bloated interface. That is, the interface is as detailed as possible, and the methods in the interface are as few as possible.

The interface segregation principle (Interface Segregation Principle, ISP) defines that the client should not rely on interfaces it does not need, and the dependency between classes should be established on the smallest interface. Simply put, it is to establish a single interface, not to create a bloated interface. That is, the interface is as detailed as possible, and the methods in the interface are as few as possible.

Synthesis means a strong "ownership" relationship, which is generally expressed as a strict relationship between the whole and the part, and the life cycle of the part and the whole is the same

Synthesis means a strong "ownership" relationship, which is generally expressed as a strict relationship between the whole and the part, and the life cycle of the part and the whole is the same

High-level modules should not rely on low-level modules, and both high-level and low-level modules should rely on abstraction. Abstraction should not depend on concreteness, concreteness should depend on abstraction. When implementing the dependency inversion principle, we need to program for the abstract layer, and inject the objects of the concrete class into other objects through Dependency Injection (DI). Dependency injection refers to when an object has a dependency relationship with oth...

High-level modules should not rely on low-level modules, and both high-level and low-level modules should rely on abstraction. Abstraction should not depend on concreteness, concreteness should depend on abstraction. When implementing the dependency inversion principle, we need to program for the abstract layer, and inject the objects of the concrete class into other objects through Dependency Injection (DI). Dependency injection refers to when an object has a dependency relationship with oth...

Before using the interface isolation principle, you must first meet the single responsibility principle. Interfaces need to be highly cohesive, that is, to improve the processing capabilities of interfaces, classes, and modules, and less public methods are released. Customized services provide only the methods that visitors need. Interface design is limited. The smaller the granularity of the interface design, the more flexible the system, but it should not be too small, otherwise it will bec...

Before using the interface isolation principle, you must first meet the single responsibility principle. Interfaces need to be highly cohesive, that is, to improve the processing capabilities of interfaces, classes, and modules, and less public methods are released. Customized services provide only the methods that visitors need. Interface design is limited. The smaller the granularity of the interface design, the more flexible the system, but it should not be too small, otherwise it will bec...

The single responsibility principle pays attention to the single responsibility of the class and the interface. The responsibility here is divided from the business logic. However, the interface isolation principle requires that when an interface is too large, we need to divide it into some smaller interfaces. Use this The client of the interface only needs to know the methods related to it. In other words, we may meet the single responsibility principle but not the interface isolation princi...

The single responsibility principle pays attention to the single responsibility of the class and the interface. The responsibility here is divided from the business logic. However, the interface isolation principle requires that when an interface is too large, we need to divide it into some smaller interfaces. Use this The client of the interface only needs to know the methods related to it. In other words, we may meet the single responsibility principle but not the interface isolation princi...

Aggregation represents a weak "ownership" relationship, which is generally expressed as a loose relationship between the whole and the part. In fact, the so-called whole and part can also be completely unrelated. For example, object A holds object B, object B is not part of object A, that is, the life cycle of object B is managed by object B itself, and is not related to object A.

Aggregation represents a weak "ownership" relationship, which is generally expressed as a loose relationship between the whole and the part. In fact, the so-called whole and part can also be completely unrelated. For example, object A holds object B, object B is not part of object A, that is, the life cycle of object B is managed by object B itself, and is not related to object A.

The definition of Dependency Inversion Principle (DIP): Programs must rely on abstract interfaces, not specific implementations. Simply put, it is required to program the abstraction, not the implementation, which reduces the coupling between the client and the implementation module. The meaning of relying on the principle of reversal The principle of dependency inversion requires us to refer to high-level abstraction classes as much as possible when passing parameters in program code or in a...

The definition of Dependency Inversion Principle (DIP): Programs must rely on abstract interfaces, not specific implementations. Simply put, it is required to program the abstraction, not the implementation, which reduces the coupling between the client and the implementation module. The meaning of relying on the principle of reversal The principle of dependency inversion requires us to refer to high-level abstraction classes as much as possible when passing parameters in program code or in a...

Only when the derived class can replace the base class and the function of the software unit is not affected, the base class can be reused, and the derived class can also add new behaviors on the basis of the base class. The Richter's Substitution Principle is a supplement to the "open-close" principle. The key step to realize the "open-close" principle is abstraction. The inheritance relationship between the base class and the subclass is the concrete realization of abstraction, so the Richt...

Only when the derived class can replace the base class and the function of the software unit is not affected, the base class can be reused, and the derived class can also add new behaviors on the basis of the base class. The Richter's Substitution Principle is a supplement to the "open-close" principle. The key step to realize the "open-close" principle is abstraction. The inheritance relationship between the base class and the subclass is the concrete realization of abstraction, so the Richt...

In fact, the reason is very simple. As long as there is an inheritance relationship, all non-private properties or methods of the base class can be obtained through inheritance (white box reuse). Or method. At this time, you cannot use the base class to obtain these new attributes or methods of the subclass. The Richter Substitution Principle is the basis for the realization of the opening and closing principle. It tells us that the base class may be used for object definition and reference w...

In fact, the reason is very simple. As long as there is an inheritance relationship, all non-private properties or methods of the base class can be obtained through inheritance (white box reuse). Or method. At this time, you cannot use the base class to obtain these new attributes or methods of the subclass. The Richter Substitution Principle is the basis for the realization of the opening and closing principle. It tells us that the base class may be used for object definition and reference w...

The Composite/Aggregate Reuse Principle (CARP) is generally called the Composite Reuse Principle (CRP), which is defined as: try to use composite/aggregate instead of inheriting to achieve the purpose of reuse. The principle of composition/aggregation reuse is to use some existing objects in a new object to make it a part of the new object; the new object achieves the purpose of reusing existing functions by delegating to these objects held internally. Instead of getting existing functions th...

The Composite/Aggregate Reuse Principle (CARP) is generally called the Composite Reuse Principle (CRP), which is defined as: try to use composite/aggregate instead of inheriting to achieve the purpose of reuse. The principle of composition/aggregation reuse is to use some existing objects in a new object to make it a part of the new object; the new object achieves the purpose of reusing existing functions by delegating to these objects held internally. Instead of getting existing functions th...

The definition of the Liskov Substitution Principle (LSP) is: all references to the base class must be able to transparently use the objects of its subclasses, or it can be simply understood as any place where the base class can appear, the subclass must be able to Appear.

The definition of the Liskov Substitution Principle (LSP) is: all references to the base class must be able to transparently use the objects of its subclasses, or it can be simply understood as any place where the base class can appear, the subclass must be able to Appear.

The single responsibility principle tells us: a class cannot do too many things. In a software system, the more responsibilities a class (a module, or a method) assumes, the lower the possibility of it being reused. A very typical example is the universal class. In fact, we can tell the truth: any conventional MVC project, in extreme cases, can use one class (or even one method) to complete all functions. But doing so will cause serious coupling and even affect the whole body. A class underta...

The single responsibility principle tells us: a class cannot do too many things. In a software system, the more responsibilities a class (a module, or a method) assumes, the lower the possibility of it being reused. A very typical example is the universal class. In fact, we can tell the truth: any conventional MVC project, in extreme cases, can use one class (or even one method) to complete all functions. But doing so will cause serious coupling and even affect the whole body. A class underta...