责任链模式

责任链模式2009-12-13 blogjava Winty
package pattern.chainofresponsibility;

/**
* 责任链模式:Chain of Responsibility
* @version 2009-5-9
* @author Winty（wintys@gmail.com）
*/
public class ChainOfResponsibilityTest{
public static void main（String[] args）{
Handler handler1 = new ConcreteHandler1（）;
Handler handler2 = new ConcreteHandler2（）;
Handler handler3 = new ConcreteHandler3（）;

//设置责任链
handler3.setSuccessor（handler2）;
handler2.setSuccessor（handler1）;

//发送命令
handler3.handleRequest（）;
}
}

/**
*抽象处理者
*/
abstract class Handler{
protected Handler successor;

public Handler getSuccessor（）{
return successor;
}

public void setSuccessor（Handler successor）{
this.successor = successor;
}

public abstract void handleRequest（）;
}

/**
*具体处理者
*/
class ConcreteHandler1 extends Handler{
public void handleRequest（）{
if（getSuccessor（） ！= null）{
System.out.print（"Request passed:from class Concrete1"）;
System.out.println（" to class" + getSuccessor（）.getClass（）.getName（））;

getSuccessor（）.handleRequest（）;
}
else{
System.out.println（"Request handled in ConcreteHandler1"）;
}
}
}

/**
*具体处理者
*/
class ConcreteHandler2  extends Handler{
public void handleRequest（）{
if（getSuccessor（） ！= null）{
System.out.print（"Request passed:from class Concrete2"）;
System.out.println（" to class " + getSuccessor（）.getClass（）.getName（））;

getSuccessor（）.handleRequest（）;
}
else{
System.out.println（"Request handled in ConcreteHandler2"）;
}
}
}

/**
*具体处理者
*/
class ConcreteHandler3  extends Handler{
public void handleRequest（）{
if（getSuccessor（） ！= null）{
System.out.print（"Request passed:from class Concrete3"）;
System.out.println（" to class " + getSuccessor（）.getClass（）.getName（））;

getSuccessor（）.handleRequest（）;
}
else{
System.out.println（"Request handled in ConcreteHandler3"）;
}
}
}