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AOP—代理对象

1．  拦截所有业务方法

2．  判断用户是否有权限，由权限就允许它执行业务方法，没有权限不允许执行业务方法。

代理对象创建由两种：静态代理，动态代理

应用的条件是目标对象必须实现接口

横切性关注点

Source:

public interface PersonService {

public void save(String name);

public void update(String name, Integer personid);

public String getPersonName(Integer personid);

}

public class PersonServiceBean implements PersonService {

private String user = null;

public PersonServiceBean() {

}

public PersonServiceBean(String user) {

this.user = user;

}

public String getPersonName(Integer personid) {

// TODO Auto-generated method stub

System.out.println("I'm getPersonName.");

return "XXX";

}

public void save(String name) {

// TODO Auto-generated method stub

System.out.println("I'm save.");

}

public void update(String name, Integer personid) {

// TODO Auto-generated method stub

System.out.println("I'm update.");

}

public String getUser() {

return user;

}

}

public class JDKProxyFactory implements InvocationHandler {

private Object targetObject;

public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {

// TODO Auto-generated method stub

PersonServiceBean bean = (PersonServiceBean) this.targetObject;

Object result = null;

if (bean.getUser() != null) {

result = method.invoke(targetObject, args);

}

return result;

}

public Object createProxyInstance(Object targetObject) {

this.targetObject = targetObject;

return Proxy.newProxyInstance(this.targetObject.getClass().getClassLoader(),

this.targetObject.getClass().getInterfaces(), this);

}

}

public class AOPTest {

@Test

public void proxyTest() {

JDKProxyFactory factory = new JDKProxyFactory();

PersonService service = (PersonService) factory.createProxyInstance(new PersonServiceBean());

service.getPersonName(1);

}

}