Decorator mode (decorator pattern) detailed

Decorator Mode (decorator pattern): dynamically attaches responsibility to an object. To extend functionality, adorners provide a more flexible alternative than inheritance.

How to use:

1. First create the component (Component) parent class , all classes, specific components (concrete Component) and adorners (decorator) belong to this type and can be extended;

Can be an abstract class (abstract Class) or an interface (interface);

Code:

/**
 * @time May 23, 2014 * * *
package decorator;

/**
 * @author C.l.wang * */public
abstract class Beverage {
	String description = "Unkown Beverage ";
	
	Public String GetDescription () {return
		description;
	}
	
	public abstract double ();
}

2. Decorator (Decorator) class parent class, Inherit component (component) parent class , but do not Implement interface function, by its inheriting class (specific adorner) to implement ,

Can be an abstract class (abstract Class) or an interface (interface);

Code:

/**
 * @time May 23, 2014 * * *
package decorator;

/**
 * @author C.l.wang * */public
abstract class Condimentdecorator extends beverage {
	public Abstract String getdescription ();

}

3. specific components (concrete Component), that is, the decorator (decorator) need to decorate the basis of the inheritance component (Component) parent class;

Code:

/** * @time May 23, 2014 * * * Package decorator; /** * @author C.l.wang * */public class Darkroast extends beverage {public darkroast () {description = "Dark Roas
	T "; }/* (non-javadoc) * @see decorator.
	Beverage#cost () */@Override public double () {//TODO auto-generated method stub return 0.99;

}/** * @time May 23, 2014 * * * Package decorator;
	/** * @author C.l.wang * */public class Decat extends beverage {public Decat () {description = "Decat"; }/* (non-javadoc) * @see decorator.
	Beverage#cost () */@Override public double () {//TODO auto-generated method stub return 1.05;

}/** * @time May 23, 2014 * * * Package decorator;
	/** * @author C.l.wang * */public class Espresso extends beverage {public Espresso () {description = "Espresso"; }/* (non-javadoc) * @see decorator.
	Beverage#cost () */@Override public double () {//TODO auto-generated method stub return 1.99; }/** * @time May 2014 23rd * * * Package decorator; /** * @author C.l.wang * */public class Houseblend extends beverage {public houseblend () {description = ' house B
	Lend Coffee "; }/* (non-javadoc) * @see decorator.
	Beverage#cost () */@Override public double () {//TODO auto-generated method stub return 89;
 }

}