request请求转换成对象。

1）前端post数据过来，key和val键值对会有很多，这个时候往后端进行插值的时候，最好将这些键值对转换成对象进行处理。

使用common-beanutils 来将前端传递过来的map直接转换成对象。

依赖jar包：

前端代码的name属性要和后端bean对象属性一致！

1   <h1>测试POST</h1>
2   <form action="/bean" method="post">
3     <input type="text" name="username">用户名字
4     <input type="password" name="passowrd">用户密码
5     <button type="submit">提交</button>
6   </form>
7   </body>
8 </html>

后端代码：

 1 package jd.com.bean_test;
 2
 3 import org.apache.commons.beanutils.BeanUtils;
 4
 5 import javax.servlet.ServletException;
 6 import javax.servlet.annotation.WebServlet;
 7 import javax.servlet.http.HttpServlet;
 8 import javax.servlet.http.HttpServletRequest;
 9 import javax.servlet.http.HttpServletResponse;
10 import java.io.IOException;
11 import java.util.Map;
12
13 @WebServlet(name = "Servlet_Bean")
14 public class Servlet_Bean extends HttpServlet {
15     protected void doPost(HttpServletRequest request, HttpServletResponse response) throws  ServletException, IOException {
16         //只能针对post请求 不乱码。
17         request.setCharacterEncoding("utf-8");
18         Map<String,String[]> data=request.getParameterMap();
19         User user_obj=new User();
20         try {
21             BeanUtils.populate(user_obj,data);
22         }catch (Exception ex){
23             ex.printStackTrace();
24             throw  new RuntimeException("转换出问题！");
25         }
26         System.out.println(user_obj);
27
28
29     }
30
31     protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
32
33     }
34 }

 1 package jd.com.bean_test;
 2
 3 public class User {
 4     private String username;
 5     private String passowrd;
 6     public  User(){}
 7
 8     public void setUsername(String username) {
 9         this.username = username;
10     }
11
12     public void setPassowrd(String passowrd) {
13         this.passowrd = passowrd;
14     }
15
16     public String getUsername() {
17         return username;
18     }
19
20     public String getPassowrd() {
21         return passowrd;
22     }
23
24     @Override
25     public String toString() {
26         return username+" "+passowrd;
27     }
28 }

原文地址：https://www.cnblogs.com/evilliu/p/8583738.html