Spring之替换Bean的返回结果,替换Bean的方法实例

Spring是一个非常强悍的框架+容器,其中有代理模式(动态代理模式)的极致体现。下面是两个比较让人感觉精彩的代码使用，重点关注main方法中的ClassPathXMlApplicationContext对象的实例化代码，替换对象方法的代码以及替换对象方法返回值的代码。具体的支持类有ASM、CGLIB、以及Spring3.0 CORE JAR.

代码如下:

MainMethod.java

 

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class MainMethod {

	

	private static StudentBiz studentBiz;




	public void setStudentBiz(StudentBiz studentBiz) {

		MainMethod.studentBiz = studentBiz;

	}




	public static void main(String[] args) {

		new ClassPathXmlApplicationContext("applicationContext.xml");

		System.out.println(studentBiz.getStudent().getName());

		studentBiz.printMsg();

	}

}

SbMethodReplacer.java

import java.lang.reflect.Method;




import org.springframework.beans.factory.support.MethodReplacer;







public class SbMethodReplacer implements MethodReplacer{




	@Override

	public Object reimplement(Object obj, Method method, Object[] args)

			throws Throwable {

		System.out.println("Hi world!!");

		return null;

	}

	

}

Student.java

public class Student {

	private String name;




	public String getName() {

		return name;

	}




	public void setName(String name) {

		this.name = name;

	}

	

}

StudentBiz.java

public interface StudentBiz {

	public Student getStudent();

	public void printMsg();

}

StudentBizImpl.java

public class StudentBizImpl implements StudentBiz {




	@Override

	public Student getStudent() {

		return null;

	}




	@Override

	public void printMsg() {

		System.out.println("hello world!!");

	}




}

applicationContext.xml

	

	

	

		anyone