Home Backend Development C#.Net Tutorial A brief introduction to C++ design patterns and appearance patterns

A brief introduction to C++ design patterns and appearance patterns

Jan 18, 2017 pm 02:52 PM

Facade mode (Facade): Provides a consistent interface for a set of interfaces in a subsystem. This mode defines a high-level interface that makes this subsystem easier to use.

Two major roles:

Appearance class Facade: Knows which subsystem classes are responsible for processing requests, and proxies customer requests to the appropriate subsystem objects.

Subsystem collection SubSystem: implements the functions of the subsystem and handles tasks assigned by the Facade object. Note: The subclass does not have any information about the Facade, that is, there is no reference to the Facade object.

This article takes the purchase of funds as an example. Customers only need to buy and sell funds (Facade), and the operations of Stock 1, Stock 2, Stock 3, etc. (SubSystem) are handled by the fund company.

Test case:

[code]int main(){
    Fund fund;//基金对象(Facade)
    fund.fundBuy();//stock1 buy stock2 buy stock3 buy
    fund.fundSell(); //stock1 sell stcok2 sell stock3 sell

    return 0;
}
Copy after login

Appearance mode implementation:

[code]//子系统不知道Facade的任何信息
//股票1号
class Stock1{
public:
    void sell(){
        std::cout << "stock1 sell\n";
    }
    void buy(){
        std::cout << "stock1 buy\n";
    }
};
//股票2号
class Stock2{
public:
    void sell(){
        std::cout << "stcok2 sell\n";
    }
    void buy(){
        std::cout << "stock2 buy\n";
    }
};
//股票3号
class Stock3{
public:
    void sell(){
        std::cout << "stock3 sell\n";
    }
    void buy(){
        std::cout << "stock3 buy\n";
    }
};

//基金类是Facade
class Fund{
public:
    Stock1 stock1;
    Stock2 stock2;
    Stock3 stock3;
    void fundSell(){
        stock1.sell();
        stock2.sell();
        stock3.sell();
    }
    void fundBuy(){
        stock1.buy();
        stock2.buy();
        stock3.buy();
    }
};
Copy after login

When to use appearance mode?

In the early stages of design, you should consciously separate the two different layers.

During the development stage, subsystems often become more and more complex due to continuous reconstruction and evolution.

When maintaining a large legacy system, you can use the highly complex code or poorly designed code of the original system to use a relatively simple and clear interface to allow the new system to interact with the Facade object.

The above is the content of the appearance mode of C++ design pattern. For more related content, please pay attention to the PHP Chinese website (www.php.cn)!


Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

C# vs. C  : History, Evolution, and Future Prospects C# vs. C : History, Evolution, and Future Prospects Apr 19, 2025 am 12:07 AM

The history and evolution of C# and C are unique, and the future prospects are also different. 1.C was invented by BjarneStroustrup in 1983 to introduce object-oriented programming into the C language. Its evolution process includes multiple standardizations, such as C 11 introducing auto keywords and lambda expressions, C 20 introducing concepts and coroutines, and will focus on performance and system-level programming in the future. 2.C# was released by Microsoft in 2000. Combining the advantages of C and Java, its evolution focuses on simplicity and productivity. For example, C#2.0 introduced generics and C#5.0 introduced asynchronous programming, which will focus on developers' productivity and cloud computing in the future.

Golang and C  : Concurrency vs. Raw Speed Golang and C : Concurrency vs. Raw Speed Apr 21, 2025 am 12:16 AM

Golang is better than C in concurrency, while C is better than Golang in raw speed. 1) Golang achieves efficient concurrency through goroutine and channel, which is suitable for handling a large number of concurrent tasks. 2)C Through compiler optimization and standard library, it provides high performance close to hardware, suitable for applications that require extreme optimization.

The Performance Race: Golang vs. C The Performance Race: Golang vs. C Apr 16, 2025 am 12:07 AM

Golang and C each have their own advantages in performance competitions: 1) Golang is suitable for high concurrency and rapid development, and 2) C provides higher performance and fine-grained control. The selection should be based on project requirements and team technology stack.

Where to write code in vscode Where to write code in vscode Apr 15, 2025 pm 09:54 PM

Writing code in Visual Studio Code (VSCode) is simple and easy to use. Just install VSCode, create a project, select a language, create a file, write code, save and run it. The advantages of VSCode include cross-platform, free and open source, powerful features, rich extensions, and lightweight and fast.

Golang and C  : The Trade-offs in Performance Golang and C : The Trade-offs in Performance Apr 17, 2025 am 12:18 AM

The performance differences between Golang and C are mainly reflected in memory management, compilation optimization and runtime efficiency. 1) Golang's garbage collection mechanism is convenient but may affect performance, 2) C's manual memory management and compiler optimization are more efficient in recursive computing.

How to run programs in terminal vscode How to run programs in terminal vscode Apr 15, 2025 pm 06:42 PM

In VS Code, you can run the program in the terminal through the following steps: Prepare the code and open the integrated terminal to ensure that the code directory is consistent with the terminal working directory. Select the run command according to the programming language (such as Python's python your_file_name.py) to check whether it runs successfully and resolve errors. Use the debugger to improve debugging efficiency.

Python vs. C  : Learning Curves and Ease of Use Python vs. C : Learning Curves and Ease of Use Apr 19, 2025 am 12:20 AM

Python is easier to learn and use, while C is more powerful but complex. 1. Python syntax is concise and suitable for beginners. Dynamic typing and automatic memory management make it easy to use, but may cause runtime errors. 2.C provides low-level control and advanced features, suitable for high-performance applications, but has a high learning threshold and requires manual memory and type safety management.

Do you use c in visual studio code Do you use c in visual studio code Apr 15, 2025 pm 08:03 PM

Writing C in VS Code is not only feasible, but also efficient and elegant. The key is to install the excellent C/C extension, which provides functions such as code completion, syntax highlighting, and debugging. VS Code's debugging capabilities help you quickly locate bugs, while printf output is an old-fashioned but effective debugging method. In addition, when dynamic memory allocation, the return value should be checked and memory freed to prevent memory leaks, and debugging these issues is convenient in VS Code. Although VS Code cannot directly help with performance optimization, it provides a good development environment for easy analysis of code performance. Good programming habits, readability and maintainability are also crucial. Anyway, VS Code is

See all articles