简单工厂

简单工厂由工厂类，抽象产品类和具体产品类组成

1.抽象产品接口

package
{
	public interface IGraph
	{
		function draw():void
	}
}

2.产品工厂类

package
{
	public class GrapFactory
	{
		public function GrapFactory()
		{
		}
		public static function factory(shape:String):IGraph
		{
			switch (shape)
			{
				case "circle":
					return new Circle();
					break;
				case "triangle":
					return new Triangle();
					break;
				default:
					throw new Error("shape is not exit");
					break;
			}
		}
	}
}

3.具体产品类

package
{
	import flash.display.Shape;

	public class Circle extends Shape implements IGraph
	{
		public var radius:Number
		public function Circle()
		{
		}
		public function draw():void
		{
			this.graphics.lineStyle(1);
			this.graphics.drawCircle(0,0,radius);
		}
	}
}

package
{
	import flash.display.Shape;
	import flash.geom.Point;

	public class Triangle extends Shape implements IGraph
	{
		public var p1:Point;
		public var p2:Point;
		public var p3:Point;
		public var p4:Point;
		public function Triangle()
		{	
		}
		public function draw():void
		{
			this.graphics.lineStyle(1);
			this.graphics.moveTo(p1.x,p1.y);
			this.graphics.moveTo(p2.x,p2.y);
			this.graphics.moveTo(p3.x,p3.y);
			this.graphics.moveTo(p1.x,p1.y);
		}
	}
}

4.调用

package
{
	import flash.display.Sprite;
	
	public class shejimoshi extends Sprite
	{
		public function shejimoshi()
		{
			var circle:Circle =  GrapFactory.factory("circle") as Circle;
			circle.radius = 20;
			circle.draw();
			addChild(circle);
		}
	}
}