3.Servlet实例

一.基础实例

1.参照如下例子创建maven web工程：

https://www.cnblogs.com/lukelook/p/9187313.html

2.创建一个简单的Servlet 类

package com.my.web;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class CallWeb
 */
public class CallWeb extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public CallWeb() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        response.getWriter().append("<p>").append("This is just a test!").append("</p>");
        response.getWriter().append("Served at: ").append(request.getContextPath());
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
    }

}
View Code

3.在web.xml中配置如下：

<?xml version="1.0" encoding="UTF-8"?>

<web-app version="3.0"

xmlns="http://java.sun.com/xml/ns/javaee"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://java.sun.com/xml/ns/javaee

http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">

 <!--如果 Servlet class 中已经用@WebServlet("/XXX")则不需要次配置，要不然会发生冲突-->

<!--
<display-name>Archetype Created Web Application</display-name>

    <servlet>
          <servlet-name>CallWeb</servlet-name>
          <servlet-class>com.my.web.CallWeb</servlet-class>
  </servlet>
  <servlet-mapping>
      <servlet-name>CallWeb</servlet-name>
      <url-pattern>/CallWeb</url-pattern>
  </servlet-mapping>
-->
</web-app>

4.Run On Server CallWeb.class

5.在浏览器中输入如下地址即可访问：

http://localhost:8080/myWeb/CallWeb

 二.表单数据提交

1.JSP界面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>show</title>
</head>
<body>
<form action="CallWeb" method="post">
<!--fieldset 对信息分组-->
<fieldset>
      <legend>个人信息:</legend>
    班级：<input list="browsers" name="stuClass">
    <datalist id="browsers">
         <option value="一一班">
         <option value="一二班">
         <option value="二一班">
         <option value="二二班">
         <option value="三一班">
    </datalist><br/><br/>
    用户名：<input type="text" name="stuName" id="stuName" value="请输入用户名"><br/><br/>
    密码：<input type="password" name="stuPassword" id="stuPassword"><br/><br/>
    <!-- label 当点击字时单选框也会被选上 -->
    性别：<input type="radio" name="sex" value="女" id="male"><label for="male">女</label>
        <input type="radio" name="sex" value="男" id="female"> <label for="female">男</label>
        <input type="radio" name="sex" value="保密" id="unknow" checked="checked"><label for="unknow">保密</label><br/><br/>
</fieldset>
<fieldset>
          <legend>其他信息:</legend>
    兴趣爱好：<input type="checkbox" name="love" value="足球 ">足球
          <input type="checkbox" name="love" value="篮球 ">篮球
          <input type="checkbox" name="love" value="排球 ">排球<br/><br/>
    地址：    <select name="address"> 
                  <optgroup label="河南省"> 
                    <option value="RuZhou">汝州</option> 
                    <option value="ZhengZhou">郑州</option> 
                  </optgroup> 
                  <optgroup label="陕西省"> 
                    <option value="XiAn">西安</option> 
                    <option value="WeiNan">渭南</option> 
                  </optgroup> 
        </select>
</fieldset>
<input type="submit" value="提交">
</form>

</body>
</html>

2.Servlet处理类

package com.my.web;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class Show
 */
@WebServlet("/CallWeb")
public class CallWeb extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public CallWeb() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        request.setCharacterEncoding("UTF-8");
        response.setCharacterEncoding("UTF-8");
        response.setContentType("text/html");
        PrintWriter pw = response.getWriter();
        pw.println("班级："+request.getParameter("stuClass")+"<br/>");
        pw.println("用户名："+request.getParameter("stuName")+"<br/>");
        pw.println("密码："+request.getParameter("stuPassword")+"<br/>");
        pw.println("性别："+request.getParameter("sex")+"<br/>");
        String[] arr=request.getParameterValues("love");
        for (String string : arr) {
            pw.println("兴趣："+string+"<br/>");
        }
        pw.println("地址："+request.getParameter("address")+"<br/>");
        
    
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
    }

}

3.界面效果

 

【推广】 免费学中医，健康全家人
原文地址：https://www.cnblogs.com/lukelook/p/9258044.html