JSP开发问题

2015-11-03 09:10:01 864 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

Java Web开发中常见的JSP类找不到问题解析与解决方案本文解析了Java Web开发中常见的org.apache.jasper.JasperException: java.lang.ClassNotFoundException问题，以ClassNotFoundException: org.apache.jsp.login_jsp为例，从文件路径、编译失败、类路径配置、Tomcat工作目录和版本兼容性五个方面分析原因，并提供详细的解决方案。作者建议检查JSP文件位置、查看Tomcat日志、清理工作目录、验证依赖项和服务器版本，同时推荐使用IDE调试和配置JSP编阅读详情

第一次开发JSP程序，按照网上介绍的教程做的表单提交程序，点提交没有反应，不知道是哪里的错，怎样调试，把页面贴出来，帮忙分析一下。
JSP页面:

JSP代码:



<%@ 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%>">

    

    <title>My JSP 'index.jsp' starting page</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">

	-->

  </head>

  

  <body>

    <format action="TestServlet">

       w3c在线教程:

       <input type="text" name="weburl" size="100"/><br/>

       <input type="submit" value="提交"/>

    </format>

  </body>

</html>

TestServlet代码:



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 TestServlet extends HttpServlet {



	private static final long serialVersionUID=-1575386983723846021L;

	public void service(HttpServletRequest request, HttpServletResponse response)

			throws ServletException, IOException {

		String weburl=request.getParameter("weburl");

		System.out.print(weburl);

		if(weburl!=null && weburl.equals("http://www.w3csschool.com"))

		{

			request.setAttribute("weburl", "你输入的是W3C在线教程网");

		}

		else

		{

			request.setAttribute("weburl", "你输入的网址在数据库中未有记录");

		}

		RequestDispatcher dispatcher=request.getRequestDispatcher("result.jsp");

		dispatcher.forward(request, response);

	}



}

web.xml配置



<?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">

  <servlet>

    <description>This is the description of my J2EE component</description>

    <display-name>This is the display name of my J2EE component</display-name>

    <servlet-name>TestServlet</servlet-name>

    <servlet-class>TestServlet</servlet-class>

  </servlet>



  <servlet-mapping>

    <servlet-name>TestServlet</servlet-name>

    <url-pattern>/servlet/TestServlet</url-pattern>

  </servlet-mapping>

  <welcome-file-list>

    <welcome-file>index.jsp</welcome-file>

  </welcome-file-list>

</web-app>

result.jsp页面:



<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

   <head>

      <title>结果是:</title>

   </head>

   

   <body>

      <%=request.getAttribute("weburl")%>

   </body>

</html>

...全文

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zhangfengyi

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切换为时间正序

zhangfengyi 2015-11-05

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这样就可以了 String name=new String(request.getParameter("Name").getBytes("ISO-8859-1"),"UTF-8");

zhangfengyi 2015-11-05

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新问题，jsp 页面与servlet页面都设置了utf-8编码，为什么中文字符还是乱码 jsp页面:


<%@page pageEncoding="utf-8" contentType="text/html;charset=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">d
<html>
  <head>
    <base href="<%=basePath%>">
    
    <title>My JSP 'index.jsp' starting page</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">
	<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />

servlet页面:


response.setContentType("text/html;charset=UTF-8");
response.setCharacterEncoding("UTF-8");

zhangfengyi 2015-11-03

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TestServlet.java如下，没有返回结果，我怎样调试


private static final long serialVersionUID=-1575386983723846021L;
	public void service(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		//String merchID=request.getParameter("MerchID");
		
		//if(merchID!=null)
		//{
		//	request.setAttribute("merchID", "你输入的是W3C在线教程网");
		//}
		//else
		//{
		//	request.setAttribute("merchID", "你输入的网址在数据库中未有记录");
		//}
		//RequestDispatcher dispatcher=request.getRequestDispatcher("result.jsp");
		//dispatcher.forward(request, response);
		
		try
		{
			//String merchid=request.getParameter("MerchID");
			//String msgid=request.getParameter("MsgID");
			//String cardno=request.getParameter("CardID");
			//System.out.println(merchid);
			//RequestDispatcher dispatcher=request.getRequestDispatcher("result.jsp");
			//dispatcher.forward(request, response);
			String cardno="6228480030976274";
			String certino="410711199002251";
			String name="王*峰";
			String phone="13918315*";
			
			String limitdate="";
			String cvn2="";
			
			String msgid=getCurrentDateTime();
			String merchid="33350018";
			String certitype="01";
			String cerPwd="1234567890";
			String deskey="6350105e40013e7de0530b14640a74e2";
			
			String url="http://101.254.166.186/certification/check";
			int conntimeout=50000;
			int sotimeout=60000;
			
			CertiRequest req=new CertiRequest();
			req.setMerchid(merchid);
			req.setMsgid(msgid);
			req.setCardno(cardno);
			req.setCertitype(certitype);
			req.setCertino(certino);
			req.setName(name);
			req.setPhone(phone);
			req.setLimitdate(limitdate);
			req.setCvn2(cvn2);
			req.setDeskey(deskey);
			req.setConntimeout(conntimeout);
			req.setSotimeout(sotimeout);
			req.setUrl(url);
			
			RequestService serv=new RequestService();
			CertiResponse resp;
			try
			{
				resp=serv.send(req);
			}
			catch(Exception e)
			{
				e.printStackTrace();
				return;
			}
			System.out.println("返回数据:"+resp.toString());
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
	
	public static String getCurrentDateTime()
	{
		SimpleDateFormat dateFormat=new SimpleDateFormat("yyyyddHHmmss");
		return String.valueOf(dateFormat.format(new Date()));
	}
	
	public static String productFigure()
	{
		Random rnd=new Random();
		int num=rnd.nextInt();
		if(num<=0 || num>999999)
		{
			return productFigure();
		}
		return String.valueOf(num);
	}

zhangfengyi 2015-11-03

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问题是解决了，还有其他问题

qq_17553329 2015-11-03

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好像解决了

I_am_a_Beginner 2015-11-03

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进来学习！

Usher丶AckMan 2015-11-03

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右击项目属性，不是有个java build paths,里面加就可以了

zhangfengyi 2015-11-03

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在TestServlet.java中怎样引用jar包


2015/09/23  19:04           263,965 commons-codec-1.9.jar
2015/09/23  18:19           305,001 commons-httpclient-3.1.jar
2015/09/23  19:03            62,050 commons-logging-1.1.3.jar
2015/01/13  10:14           313,898 dom4j-1.6.1.jar
2015/01/11  13:45           489,884 log4j-1.2.17.jar
2015/10/10  11:33            23,573 payCheck-1.0.1.jar

zhangfengyi 2015-11-03

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是路径的问题，改了下路径就可以了，配置文件中的路径<url-pattern>/TestServlet</url-pattern>，改成这样的就可以了

执笔记忆的空白 2015-11-03

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你把action的值改一下，改成这个/servlet/TestServlet

sinat_31535993 2015-11-03

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引用 2 楼 zhangfengyi 的回复:

[quote=引用 1 楼 sinat_31535993 的回复:] <format action="TestServlet"> w3c在线教程: <input type="text" name="weburl" size="100"/><br/> <input type="submit" value="提交"/> </format> 第一次见form表单写成format的

写错了，问题又来了，这个路径如何写

[/quote] <url-pattern>/servlet/TestServlet</url-pattern>这不就是你自己设置的路径！

zhangfengyi 2015-11-03

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引用 1 楼 sinat_31535993 的回复:

<format action="TestServlet">
w3c在线教程:
<input type="text" name="weburl" size="100"/><br/>
<input type="submit" value="提交"/>
</format>
第一次见form表单写成format的

写错了，问题又来了，这个路径如何写

sinat_31535993 2015-11-03

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<format action="TestServlet"> w3c在线教程: <input type="text" name="weburl" size="100"/><br/> <input type="submit" value="提交"/> </format> 第一次见form表单写成format的

心随自在飞 2015-11-03

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设段点，debug模式！一步一步慢慢走！

朗晴 2015-11-03

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多看多练加油。

JSP开发问题

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