JDK提供的动态代理
提供接口和实现类
package cn.chen.proxy.jdk;
public interface UserMgr {
void addUser();
}
package cn.chen.proxy.jdk;
public class UserMgrImpl implements UserMgr {
@Override
public void addUser() {
System.out.println("1.插入记录到User表");
System.out.println("2.做日志在另外一张表");
}
}
对代理类进行处理
package cn.chen.proxy.jdk;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
public class TransProxyByJDK implements InvocationHandler{
private Object target;
public TransProxyByJDK(Object target) {
this.target = target;
}
@Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
System.out.println("transacation start");
method.invoke(target, args);
System.out.println("transacation commit");
return null;
}
}
测试
package cn.chen.proxy.jdk;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Proxy;
public class Client {
public static void main(String[] args) throws Exception {
UserMgr userMgr = new UserMgrImpl();
InvocationHandler h = new TransProxyByJDK(userMgr);
UserMgr u = (UserMgr) Proxy.newProxyInstance(userMgr.getClass().getClassLoader() ,new Class[]{UserMgr.class}, h);
u.addUser();
}
}
transacation start
1.插入记录到User表
2.做日志在另外一张表
transacation commit
Process finished with exit code 0
JDK的动态代理中代理类必须实现接口,cglib实现动态代理则不用:cglib实现动态代理