struts2源码阅读一

   看了下struts2的访问拦截器的机制，自己写了段类似的代码

public interface Test {
    public String test(TestInvocation invocation);
}
public class Test1 implements Test {

	@Override
	public String test(TestInvocation invocation) {
		// TODO Auto-generated method stub
          System.out.println("hello!in test1");
          return invocation.invoke();
	}

}

public class Test2 implements Test {

	@Override
	public String test(TestInvocation invocation) {
		// TODO Auto-generated method stub
        System.out.println("hello in test2");
        return invocation.invoke();
	}

}

Test接口         对应struts2中的Interceptor接口.
TestInvocation 对应struts2中的ActionInvocation

public class DefaultInvocation implements TestInvocation{
    public Iterator interceptors;
    public String result;
	public String invoke() {
		// TODO Auto-generated method stub
		if(interceptors.hasNext()){
			Test test=(Test)interceptors.next();
			result=test.test(this);
			
		}
		else
			return "end";
		return null;
	}
	public void init(){
		Test t1=new Test1();
		Test t2=new Test2();
		List<Test> tlist=new ArrayList<Test>();
		tlist.add(t1);
		tlist.add(t2);
		interceptors=tlist.iterator();
	}
	
	public static void main(String[] args){
		DefaultInvocation inc=new DefaultInvocation();
		inc.init();
		inc.invoke();
	}
    
}

更详细的一篇
http://blog.csdn.net/leisure55/archive/2009/08/05/4410387.aspx