Servlet 第一个DEMO

学习servlet的一个demo：

1.环境配置：

用的是tomcat7.0和myeclipse8.5，怎么安装怎么配置就不说了，有一个问题是8.5没有tomcat选项，配置6.x的时候在运行时报错，修改方法：

window --》preference--》MyEclipse--》server--》tomcat--》tomcat6.x--》paths--》append to classpath 添加tomcat7.0 bin目录下的tomcat-juil.jar文件即可

2.实例

2.1 HelloServlet:

package servletTest.servlet;

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

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class HelloServlet extends HttpServlet {

	private static final long serialVersionUID = 1L;

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		/************* 处理中文乱码的问题 ***********************/
		req.setCharacterEncoding("UTF-8");
		resp.setContentType("text/html;charset=UTF-8");
		
		String inputSting = req.getParameter("inputString");
		System.out.println("00 inputString = " + inputSting);
		
		RequestDispatcher dispatcher = req.getRequestDispatcher("/jsp/result.jsp");
		req.setAttribute("inputString", inputSting);
		dispatcher .forward(req, resp); 
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(req, resp);
	}

	@Override
	public void destroy() {
		// TODO Auto-generated method stub
		super.destroy();
	}

	@Override
	public void init() throws ServletException {
		// TODO Auto-generated method stub
		super.init();
	}

}

2.2 index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>" target="_blank" rel="external nofollow"  target="_blank" rel="external nofollow" >
    
    <title>index.jsp</title>
	<meta http-equiv="pragma" content="no-cache">
	<meta http-equiv="cache-control" content="no-cache">
	<meta http-equiv="expires" content="0">    
	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
	<meta http-equiv="description" content="This is my page">
	<!--
	<link rel="stylesheet" type="text/css" href="styles.css" target="_blank" rel="external nofollow"  target="_blank" rel="external nofollow" >
	-->
  </head>
  
  <body>
  	<p> 请输入一个字符串吧：
  	<%=basePath %>
    <form action="HelloServlet" method="post">
    	<input type="text" name="inputString" /><br/>
    	
    	<input type="submit" value=" 提交  ">
    </form>
  </body>
</html>

2.3 jsp/result.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>" target="_blank" rel="external nofollow"  target="_blank" rel="external nofollow" >
    
    <title>result.jsp</title>
    
	<meta http-equiv="pragma" content="no-cache">
	<meta http-equiv="cache-control" content="no-cache">
	<meta http-equiv="expires" content="0">    
	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
	<meta http-equiv="description" content="This is my page">
	<!--
	<link rel="stylesheet" type="text/css" href="styles.css" target="_blank" rel="external nofollow"  target="_blank" rel="external nofollow" >
	-->

  </head>
  
  <body>
    <%
    	String inputString = (String)request.getAttribute("inputString");
    %>
    <p>输入的字符窜为：<%= inputString %>
  </body>
</html>

2.4 web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
	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_2_5.xsd">
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
  
  <!-- HelloServlet 配置 -->
  <servlet>
  	<servlet-name>HelloServlet</servlet-name>
  	<servlet-class>servletTest.servlet.HelloServlet</servlet-class>
  </servlet>
  
  <servlet-mapping>
  	<servlet-name>HelloServlet</servlet-name>
  	<url-pattern>/HelloServlet</url-pattern>
  </servlet-mapping>
  
</web-app>