一个Servelt多个请求
基础模拟
方法一：使用switch方法
一、方法介绍
- 方法：switch
- 优点：方法简单，明了
- 缺点：维护麻烦，保密性不好
二、代码实现
1、servlet类
package servlet; /** * 使用参数进行多个请求 */ import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; @WebServlet("/CustomerServelet") public class CustomerServelet extends HttpServlet { protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String method=request.getParameter("method"); switch (method){ case "add": add(request,response); break; case "update": update(request,response); break; case "delet": delet1(request,response); break; default: break; } }
//删除 private void delete(HttpServletRequest request, HttpServletResponse response) { System.out.println("delete"); } //更新 private void update(HttpServletRequest request, HttpServletResponse response) { System.out.println("update"); } //添加 private void add(HttpServletRequest request, HttpServletResponse response) { System.out.println("add"); } protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request,response); } }
2、jsp测试文件
<body> <a href="CustomerServelet?method=add">Add</a> <a href="CustomerServelet?method=update">Update</a> <a href="CustomerServelet?method=delete">Delete</a> </body>
方法二：使用Java反射方法
一、方法介绍
- 方法：Java反射
- 优点：保密性好，易于维护
- 缺点：比较麻烦
二、代码实现
1、servlet类
package servlet; import mvcdemo.CriteriaCustomer; import mvcdemo.CustomerDAO; import mvcentity.Customer; import mvcimpl.CustomerDAOJdbcImpl; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.lang.reflect.Method; import java.util.List; @WebServlet("*.do") //或者 //@WebServlet("*.do")//符合“*.do”的格式，则映射到里面。 public class CustomerServelet1 extends HttpServlet { private static final long serialVersionUID=1L; private CustomerDAO customerDAO=new CustomerDAOJdbcImpl(); protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //得到请求路径,格式为“/add.do” String serveletPath=request.getServletPath(); //格式路径，获取方法名 String methodName=serveletPath.substring(1);//此时格式“*.do" methodName=methodName.substring(0,methodName.length()-3);//此时格式"*" //利用反射获取methodName对应的方法 try{ Method method=getClass().getDeclaredMethod(methodName,HttpServletRequest.class,HttpServletResponse.class); method.invoke(this,request,response); }catch (Exception e){ e.printStackTrace(); } } //删除private void delete(HttpServletRequest request, HttpServletResponse response) throws ServletException,IOException{ System.out.println("delete"); }
//更新 private void update(HttpServletRequest request, HttpServletResponse response) throws ServletException,IOException{ System.out.println("update"); } //增加private void add(HttpServletRequest request, HttpServletResponse response) throws ServletException,IOException{ System.out.println("add"); } protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doPost(request,response); } }
2、jsp测试文件
<body>
<a href="add.do">Add</a>
<a href="update.do">Update</a>
<a href="delete.do">Delete</a>
</body>
三、说明
当运行jsp文件，并且点击其超链接，可以在控制台中显示出，相应的数据说明成功