1、利用Proxy實現用戶權限控制;
接口類
package cn.ts.service; public interface PersonService { public void save(String name); public void update(String name, Integer personid); public String getPersonName(Integer personid); }
實現接口類:
package cn.ts.service;
import cn.ts.service.PersonService;
public class PersonServiceBean implements PersonService{
private String user = null;
public String getUser() {
return user;
}
public PersonServiceBean(){}
public PersonServiceBean(String user){
this.user = user;
}
public String getPersonName(Integer personid) {
System.out.println("我是getPersonName()方法");
return "xxx";
}
public void save(String name) {
System.out.println("我是save()方法");
}
public void update(String name, Integer personid) {
System.out.println("我是update()方法");
}
}
Proxy實現的代理類:
package cn.ts.aop;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import cn.ts.service.PersonServiceBean;
public class JDKProxyFactory implements InvocationHandler{
private Object targetObject;
public Object createProxyIntance(Object targetObject){
this.targetObject = targetObject;
return Proxy.newProxyInstance(this.targetObject.getClass().getClassLoader(),
this.targetObject.getClass().getInterfaces(), this);
}
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable {//環繞通知
PersonServiceBean bean = (PersonServiceBean) this.targetObject;
Object result = null;
if(bean.getUser()!=null){
//..... advice()-->前置通知
try {
result = method.invoke(targetObject, args);
// afteradvice() -->後置通知
} catch (RuntimeException e) {
//exceptionadvice()--> 例外通知
}finally{
//finallyadvice(); -->最終通知
}
}
return result;
}
}
cglib.jar實現的代理類:
import java.lang.reflect.Method;
import cn.ts.service.PersonServiceBean;
import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;
public class cglibProxyFactory implements MethodInterceptor{
private Object targetObject;
public Object createProxyIntance(Object targetObject){
this.targetObject = targetObject;
Enhancer enhancer = new Enhancer();
enhancer.setSuperclass(this.targetObject.getClass());//非final
enhancer.setCallback(this);
return enhancer.create();
}
public Object intercept(Object proxy, Method method, Object[] args,
MethodProxy methodProxy) throws Throwable {
PersonServiceBean bean = (PersonServiceBean) this.targetObject;
Object result = null;
if(bean.getUser()!=null){
result = methodProxy.invoke(targetObject, args);
}
return result;
}
}
測試類:
package cn.ts.junit;
import org.junit.BeforeClass;
import org.junit.Test;
import cn.ts.aop.JDKProxyFactory;
import cn.ts.aop.cglibProxyFactory;
import cn.ts.service.PersonService;
import cn.ts.service.PersonServiceBean;
public class AOPTest {
@BeforeClass
public static void setUpBeforeClass() throws Exception {
}
@Test public void proxyTest(){
JDKProxyFactory factory = new JDKProxyFactory();
PersonService service = (PersonService) factory.createProxyIntance(new PersonServiceBean("xxx"));
service.save("888");
}
@Test public void proxyTest2(){
cglibProxyFactory factory = new cglibProxyFactory();
PersonServiceBean service = (PersonServiceBean) factory.createProxyIntance(new PersonServiceBean("eee"));
service.save("999");
}
}
兩種實現方式的區別在於:JDK的Proxy類的實現一個接口。cglib.jar則不定要實現某個接口;