java servlet 代码样例 (demo)
今天又搞了下jsp +servlet 的代码样例,感觉虽然搭了好多次,可是每次还是不记得那些参数,都要去网上搜索,索性自己把这次的简单demo给记录下来,供下次使用的时候直接复制吧。
这个web逻辑 input.jsp ---->ReportServlet -->output.jsp (在servlet中输入值,将参数传递到output.jsp中)
整个文档目录结构如下:
相关代码如下:
input.jsp:
<%@ 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=ISO-8859-1"> <title>Insert title here</title> </head> <body> <form method="post" action="report" > <p> seller_id</p> <input type="text" name="seller_id"></input> <label for="from_date">from_date:</label> <input type="text" id="from_date" name="from_date" /> <label for="end_date">end_date:</label> <input type="text" id="end_date" name="end_date" /> <input type="submit" id="submit" name="submit" /> </form> </body> </html>
output.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@ page import="java.util.*"%> <!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=ISO-8859-1"> <title>Insert title here</title> </head> <body> <% List<String> result =(List)request.getAttribute("result"); %> <table> <% for(String str:result) { %> <tr> <td> <%=str+"\n" %> </td> </tr> <%} %> </table> </body> </html>
web.xml(主要是注意servlet配置)
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>Report</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>reportServlet</servlet-name>
<servlet-class>cn.edu.ReportServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>reportServlet</servlet-name>
<url-pattern>/report</url-pattern>
</servlet-mapping>
</web-app>
ReportServlet.java 内容
package cn.edu; import java.io.IOException; import java.io.PrintWriter; import java.util.ArrayList; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; public class ReportServlet extends HttpServlet{ public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request,response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String from_date = request.getParameter("from_date"); System.out.println(from_date); List <String> result = new ArrayList<String>(); result.add("apple"); result.add("apple"); result.add("apple"); result.add("apple"); //HttpSession session=request.getSession(); request.setAttribute("result", result); request.getRequestDispatcher("output.jsp").forward(request,response); //return ; //response.sendRedirect("/Report/output.jsp"); //request. //response.sendRedirect(arg0) // response.setContentType("text/html;charset=utf-8"); // PrintWriter out = response.getWriter(); // request.setCharacterEncoding("utf-8"); // out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">"); // out.println("<HTML>"); // out.println(" <HEAD><TITLE>display survey information</TITLE></HEAD>"); // out.println(" <BODY>"); // out.println("<h2>用户输入的信息</h2>"); // out.println("用户名:"+request.getParameter("name")+"<br>"); // out.println("e-mail:"+request.getParameter("email")+"<br>"); // out.println("年纪:"+request.getParameter("age")+"<br>"); // out.println("编程时间:"+request.getParameter("codetime")+"<br>"); // out.println("你使用的操作系统:"); // printValues(out,request.getParameterValues("os")); // out.println("你使用的编程语言:"); // printValues(out,request.getParameterValues("language")); // out.println("建议:"+request.getParameter("comment")+"<br>"); // out.println(" </BODY>"); // out.println("</HTML>"); // out.flush(); // out.close(); } public void printValues(PrintWriter out,String[] values){ if(values==null || values.length==0) return; out.println("<ul>"); for(int i=0;i<values.length;i++){ out.println("<li>"+values[i]+"</li>"); } out.println("</ul>"); } }
好了,就这样了,祝学习web的朋友们好运。
每天进步一点点。