Factory method of Factory factory model FactoryMethod

Factory approach (Factory method)
* Factory method puts different products in different factory classes that implement the Factory interface (Factoryaimpl,factorybimpl ... Inside
* So even if one of the factory class is out of the question, other factory classes will work and not be affected by each other.
* After adding new products, you only need to add a factory interface factory class, can be achieved without modifying the existing code

Code Explanation:

1. Create product interface products and create 2 product sub-categories Android phones, Apple phones, all implement the Product interface

 Public Interface  Product {    }

Product {public    Android () {        System.out.println ("Production of an Android phone ...");}    }

Product {public    apple () {        System.out.println ("Producing an Apple phone ...");}    }

2. Create a factory interface, add a production method (return value is product), and create a corresponding factory implementation class for each product

 Public Interface  Factory {        /**     * produces a product      @return*/      Public       Product process ();}

 public  class  androidfactory implements   Factory  {@Override  Span style= "color: #0000ff;"  >public   Product  process () { return  new   Android (); }}

 Public class Implements  Factory {    @Override    public   Product process () {          Returnnew  Apple ();}    }

3. Client invocation: Test

 Public Static void Main (string[] args) {//        Factory Factory = new Applefactory (); // Apple Factory        New androidfactory (); // Android Factory         factory.process ();    }

In this way, only the new Xxxfactory () can be modified to produce the corresponding product of the plant.

Defects
* Factory method for each type of product (such as mobile phone class, car class ...) ) Each implementation class (such as the mobile phone class [Android factory, Apple Factory] car class [BMW factory, Mercedes-Benz Factory]) to create a corresponding factory class, when there are hundreds of or even thousands of products, also must have the corresponding hundreds of thousands of factory class, which there is a legend of the class explosion , For future maintenance, it is simply a disaster .....

Factory Method Factory Factory mode FactoryMethod