http://hi.baidu.com/hammerc/blog/item/f82925d7e792afcba144dfbd.html
在《殿堂之路》中黑羽给的网站已经下载不了，但是里面给出了源码，可以自己写成类进行使用。下面就将这些代码放上来，方便以后查找。
一共有三个类，分别是AbstractError ，strictIs，AbstractEnforcer
=====================第一个类AbstractError============================
package com.mimswright.errors
{
/**
* An error class used to ensure the correct behavior of asbsract classes.
*
* @author Mims Wright
*/
public class AbstractError extends Error
{
/**
* Use this error in the constructor for your abstract class.
*/
public static const CONSTRUCTOR_ERROR:String="ERROR: An abstract class may not be instantiated.";
/**
* Use this error in abstract methods that should be overridden in your abstract class.
*/
public static const METHOD_ERROR:String="ERROR: Failed to implement an abstract method.";
public function AbstractError(message:String="", id:int=0)
{
super(message, id);
}
}
}
=====================第二个类StrictIs===================================================
package com.mimswright.utils
{
import flash.utils.*;
/**
* Checks the class of <code>instance</code> against the <code>compareClass</code> for strict
* equality. If the classes are exactly the same, returns true. If
* the classes are different even if the <code>instance</code>'s class is a subclass
* of <code>compareClass</code>, it returns false.
* Does not work with interfaces. The compareClass must be a class.
*
* @author Mims Wright
*
* @example <listing version="3.0">
* var myBase:BaseClass = new BaseClass();
* var mySub:SubClass = new SubClass();
* trace(strictIs(myBase, BaseClass)); // true
* trace(strictIs(mySub, SubClass)); // true
* trace(strictIs(mySub, BaseClass)); // false
* </listing>
*
* @param instance - the object whos class you want to check.
* @param compareClass - the class to compare your object against.
* @return true if instance is strictly of type compareClass.
*/
public function strictIs(instance:Object, compareClass:Class):Boolean
{
var instanceClass:Class=Class(getDefinitionByName(getQualifiedClassName(instance)));
return instanceClass == compareClass;
}
}
=====================第三个类AbstractEnforcer======================================
package com.mimswright.utils
{
import com.mimswright.utils.strictIs;
import com.mimswright.errors.AbstractError;
public class AbstractEnforcer
{
public static function enforceConstructor(instance:Object, className:Class):void
{
if (strictIs(instance, className))
{
throw(new AbstractError(AbstractError.CONSTRUCTOR_ERROR));
}
}
public static function enforceMethod():void
{
throw(new AbstractError(AbstractError.METHOD_ERROR));
}
}
}
使用方法：
package org.kingda.book.basicoop.abstractclassandinterface
{
import com.mimswright.utils.AbstractEnforcer;
public class AbstractFoo
{
//抽象类的构造函数
public function AbstractFoo() {
AbstractEnforcer.enforceConstructor(this,AbstractFoo);
//trace ("ok");
}
//抽象方法
public function hello():void {
AbstractEnforcer.enforceMethod();
//trace ("hello()");
}
}
}
