在开发中,对页面的请求要创建对个servlet来进行处理,一个servlet只能处理一个请求,这样要创建多个servlet,不利于开发和以后程序的维护,我们可以对同一个模块进行合并创建一个servlet即可,比如登录模块,商品模块,订单模块等等.只需要他们继承BaseServlet,并在前台页面传递所调用的方法名即可.
package cn.itcast.stroe.utils;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class BaseServlet extends HttpServlet{
@Override
protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
//1、获取方法名
String methodName = request.getParameter("methodName");
//2、获取当前运行类的class对象
Class clazz = this.getClass();
//3、动态获取方法对象
if(methodName!=null&&!"".equals(methodName)){
try {
Method method = clazz.getMethod(methodName, HttpServletRequest.class,HttpServletResponse.class);
//执行
String path = (String) method.invoke(this, request,response);
//判断 是否需要请求转发
if(path!=null&&!"".equals(path)){
//请求转发
request.getRequestDispatcher(path).forward(request, response);
return;
}
} catch (NoSuchMethodException e) {
e.printStackTrace();
System.out.println("你需要的方法不存在");
} catch (SecurityException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
}
}
}