模拟struts2的拦截器的流程

 

 

package com.tch.test.struts2.interceptor;

import java.util.Iterator;
import java.util.List;

public class ActionInvocation {
	
	private List<Interceptor> interceptors;
	private Iterator<Interceptor> iterator;

	public void invoke(){
		if(hasNext()){
			getInterceptor().intercept(this);
		}else{
			System.out.println("调用action方法");
		}
	}

	Interceptor getInterceptor(){
		return iterator.next();
	}
	private boolean hasNext() {
		return iterator.hasNext();
	}

	public List<Interceptor> getInterceptors() {
		return interceptors;
	}

	public void setInterceptors(List<Interceptor> interceptors) {
		this.interceptors = interceptors;
		this.iterator = interceptors.iterator();
	}
	
}

 

package com.tch.test.struts2.interceptor;

public interface Interceptor {

	void intercept(ActionInvocation invocation);
	
}

 

package com.tch.test.struts2.interceptor;

public class FirstInterceptor implements Interceptor {

	@Override
	public void intercept(ActionInvocation invocation) {
		System.out.println("begin >>> first...");
		invocation.invoke();
		System.out.println("end  <<<  first");
	}

}

 

package com.tch.test.struts2.interceptor;

public class SecondInterceptor implements Interceptor {

	@Override
	public void intercept(ActionInvocation invocation) {
		System.out.println("begin >>> second...");
		invocation.invoke();
		System.out.println("end  <<<  second");
	}

}

 

package com.tch.test.struts2.interceptor;

public class ThirdInterceptor implements Interceptor {

	@Override
	public void intercept(ActionInvocation invocation) {
		System.out.println("begin >>> third...");
		invocation.invoke();
		System.out.println("end  <<<  third");
	}

}

 

package com.tch.test.struts2.interceptor;

public class FourthInterceptor implements Interceptor {

	@Override
	public void intercept(ActionInvocation invocation) {
		System.out.println("begin >>> fourth...");
		invocation.invoke();
		System.out.println("end  <<<  fourth");
	}

}

 

package com.tch.test.struts2.interceptor;

import java.util.ArrayList;
import java.util.List;

public class TestInterceptor {

	public static void main(String[] args) {
		List<Interceptor> interceptors = new ArrayList<Interceptor>();
		FirstInterceptor first = new FirstInterceptor();
		SecondInterceptor second = new SecondInterceptor();
		ThirdInterceptor third = new ThirdInterceptor();
		FourthInterceptor fourth = new FourthInterceptor();
		interceptors.add(first);
		interceptors.add(second);
		interceptors.add(third);
		interceptors.add(fourth);
		ActionInvocation invocation = new ActionInvocation();
		invocation.setInterceptors(interceptors);
		invocation.invoke();
	}
	
}

 

 

OK。。。