Design mode (decorative mode)

Decoration mode is used to add properties dynamically and flexibly to an object, consisting mainly of the following roles:

• Component: defines an object interface that can dynamically add responsibilities to these objects, in this case the product
• Concretecomponent: The specific object to be added, in this case the Productimpl, the attribute is added by AddAttribute
• Decorator: The abstraction of the adorner, maintaining a component pointer, and inheriting the pointer; In this case, the Basechange
• Concretecomponent: Specific adorners, in this case Onechange and Twochange

The code is as follows:

• Product

 Public Interface Product {    publicvoid  AddAttribute ();}

• Productimpl

 Public class Implements Product {    @Override    publicvoid  AddAttribute () {        System.out.println ("Add base Attribute");}    }

• Basechange

 Public class Implements Product {        private  product product;          Public Basechange (product product) {        this. Product= product;    }    @Override    publicvoid  AddAttribute () {        product.addattribute ();    }}

• Onechange && Twochange

 public  class  onechange extends   Basechange { public  Span style= "color: #000000;" > Onechange (product product) { super   (pro    Duct); } @Override  public  void   AddAttribute () { super  .addattribute ()        ;    SYSTEM.OUT.PRINTLN ( one change ); }}

 Public class extends Basechange {        public  twochange (product product) {        Super(product);    }        @Override      Public void AddAttribute () {        super. AddAttribute ();        System.out.println ("Change");}    }

• App

 Public class App {    publicstaticvoid  main (string[] args) {        new Productimpl ();                 New Twochange (new  onechange (product));        Change.addattribute ();    }}

The output is:

ADD Base Attributeone changetwo Change

Design mode (decorative mode)