What is adapter mode?
Adapter Pattern
The Adapter pattern is also called the adapter pattern. It is one of the structural patterns. Existing classes can be changed through the Adapter pattern ( or external class) interface form.
Adapter pattern application scenarios
In the process of large-scale system development, we often encounter situations such as the following:
We need to implement a certain These functions already have one or more external components that are not yet mature. If we re-develop these functions ourselves, it will take a lot of time; so in many cases we will choose to use external components temporarily and then consider replacing them at any time later. But this will bring about a problem. With the replacement of the external component library, it may be necessary to make extensive modifications to the source code that references the external component, so it is very likely to introduce new problems and so on. How to minimize the modification area? The Adapter pattern was proposed for this similar need. The Adapter pattern transparently calls external components by defining a new interface (which abstracts the functions to be implemented) and an Adapter class that implements the interface. In this way, when replacing external components, you only need to modify a few Adapter classes at most, and other source codes will not be affected.
php example
Suppose we have an article class that has completed the list of articles and detailed information display:
<?php
class article{
//文章列表获取方法
public function getLIst(){
echo '获取文章列表';
}
//根据文章id获取文章的标题和内容
public function getInfo($id){
echo '根据文章id获取文章的标题和内容';
}
}
$art = new article();
$art->getInfo(1);Due to the needs of the project, Such a function is now needed. When obtaining article details, you also need to obtain the creation time of the article and update the number of times the article has been read.
If we do not use the adapter mode, our first thought is to modify the source code of the article class to add such a function. The reason why I think this is because the example code above is very simple. What if it is thousands of lines? What if the getInfo() code is very complex?
Use the adapter pattern to solve all this!
class articleAdapter{
public $_artObj;
public function __construct($artObj){
$this->_artObj = $artObj;
}
public function getInfo($id){
$this->_artObj->getInfo($id);
}
public function getInfoAndUpdate($id){
//利用$this->_artObj查询符合要求的文章数据并更新浏览次数
echo '$this->_artObj查询符合要求的文章数据并更新浏览次数';
}
}
$art = new articleAdapter(new article());
$art->getInfo(12);
$art->getInfoAndUpdate(12);Why not use inheritance?
Object adapter: It is not processed through inheritance, but through object combination. As long as we have studied OO design principles, we all know that combination is the recommended way compared to inheritance. .
Class adapter: implemented through inheritance, encapsulating the methods of the old system. In the process of converting object adapters between adapters, class adapters can undoubtedly be completed, but the dependencies will increase, and with the flexibility of adaptation requirements, the expansion may become difficult to control through inheritance.
Generally speaking, class adapters are less flexible, while object adapters are more flexible. This is the recommended method. It can be done through dependency injection or configuration. The class adapter needs to inherit from the class of the old system to be adapted, which is undoubtedly not a good idea.
The above is the detailed content of What is adapter mode?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1664
14
1422
52
1316
25
1266
29
1239
24
PHP and Python: Comparing Two Popular Programming Languages
Apr 14, 2025 am 12:13 AM
PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.
PHP in Action: Real-World Examples and Applications
Apr 14, 2025 am 12:19 AM
PHP is widely used in e-commerce, content management systems and API development. 1) E-commerce: used for shopping cart function and payment processing. 2) Content management system: used for dynamic content generation and user management. 3) API development: used for RESTful API development and API security. Through performance optimization and best practices, the efficiency and maintainability of PHP applications are improved.
Explain secure password hashing in PHP (e.g., password_hash, password_verify). Why not use MD5 or SHA1?
Apr 17, 2025 am 12:06 AM
In PHP, password_hash and password_verify functions should be used to implement secure password hashing, and MD5 or SHA1 should not be used. 1) password_hash generates a hash containing salt values to enhance security. 2) Password_verify verify password and ensure security by comparing hash values. 3) MD5 and SHA1 are vulnerable and lack salt values, and are not suitable for modern password security.
PHP: A Key Language for Web Development
Apr 13, 2025 am 12:08 AM
PHP is a scripting language widely used on the server side, especially suitable for web development. 1.PHP can embed HTML, process HTTP requests and responses, and supports a variety of databases. 2.PHP is used to generate dynamic web content, process form data, access databases, etc., with strong community support and open source resources. 3. PHP is an interpreted language, and the execution process includes lexical analysis, grammatical analysis, compilation and execution. 4.PHP can be combined with MySQL for advanced applications such as user registration systems. 5. When debugging PHP, you can use functions such as error_reporting() and var_dump(). 6. Optimize PHP code to use caching mechanisms, optimize database queries and use built-in functions. 7
What are HTTP request methods (GET, POST, PUT, DELETE, etc.) and when should each be used?
Apr 09, 2025 am 12:09 AM
HTTP request methods include GET, POST, PUT and DELETE, which are used to obtain, submit, update and delete resources respectively. 1. The GET method is used to obtain resources and is suitable for read operations. 2. The POST method is used to submit data and is often used to create new resources. 3. The PUT method is used to update resources and is suitable for complete updates. 4. The DELETE method is used to delete resources and is suitable for deletion operations.
Explain the difference between self::, parent::, and static:: in PHP OOP.
Apr 09, 2025 am 12:04 AM
In PHPOOP, self:: refers to the current class, parent:: refers to the parent class, static:: is used for late static binding. 1.self:: is used for static method and constant calls, but does not support late static binding. 2.parent:: is used for subclasses to call parent class methods, and private methods cannot be accessed. 3.static:: supports late static binding, suitable for inheritance and polymorphism, but may affect the readability of the code.
How does PHP handle file uploads securely?
Apr 10, 2025 am 09:37 AM
PHP handles file uploads through the $\_FILES variable. The methods to ensure security include: 1. Check upload errors, 2. Verify file type and size, 3. Prevent file overwriting, 4. Move files to a permanent storage location.
How does PHP type hinting work, including scalar types, return types, union types, and nullable types?
Apr 17, 2025 am 12:25 AM
PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values and handle functions that may return null values.
