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();//此时格式“*.do"
methodName=methodName.substring(,methodName.length()-);//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