jsp 自写义类

Question

这是错误信息，严重: Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: Unable to compile class for JSP: An error occurred at line: 33 in the jsp file: /WebRoot/index.jsp
Detail cannot be resolved to a type
30:              <span class="one" >论坛</span><span class="two" >主题</span><span class="three" >最后发表时间</span>
31:             </div><!--title end-->
32:             <%
33:              Detail board = new Detail();
34:              board.findIndex();
35:              %>
36:              <%--
An error occurred at line: 33 in the jsp file: /WebRoot/index.jsp
Detail cannot be resolved to a type
30:              <span class="one" >论坛</span><span class="two" >主题</span><span class="three" >最后发表时间</span>
31:             </div><!--title end-->
32:             <%
33:              Detail board = new Detail();
34:              board.findIndex();
35:              %>
36:              <%--
Stacktrace:
at org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:92)
at org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:330)
at org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:423)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:316)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:294)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:281)
at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:566)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:317)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:337)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Unknown Source)找了好几天了还是找不到，郁闷 ~~~

Answer 1

 Detail board = new Detail(); 你的这个类存在吗？

Answer 2

<%@ page language="java" import="Detail的类路径" pageEncoding="UTF-8"%>

Answer 3

问题就是页面上找不到Detail类，必须先倒入才能再页面里面创建~至于导入的方法~LS说的很清楚了

Answer 4

我引入的外部类，
<%@ page import="dao.*"%>
在JSP页面里面用
<%
33:            Detail board = new Detail();
34:            board.findIndex();
35:              %> 这样写的

Answer 5

是 dao.* 里有Detail 么？

Answer 6

33:            Detail board = new Detail(); 
34:            board.findIndex(); 
有两种可能行
1。Detail类没有引用对，或者根本就没有该类，类本身有错误。
2。类中的findIndex（）方法有错误

Answer 7

package finding;import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.HashMap;
import java.util.Map;import dao.BaseDao;public class Detail {
// Connection con=null;
// Statement state=null;
// ResultSet rs=null;
//
// /*主页设置*/
// public Map findIndex() {
// Map result=new HashMap();
// int i=0;
//
// con = BaseDao.getConn();
// state = BaseDao.getStatement(con);
// rs = BaseDao.getResultSet(state, "select * from board");
//
// try {
// while(rs.next()){
// result.put(i++,rs.getString(2));
// }
// } catch (SQLException e) {
// // TODO Auto-generated catch block
// e.printStackTrace();
// }
// return result;
// }

public void findIndex() {
System.out.println("wq lasjk");

}
}

Answer 8

这是detail类下面是JSP页面<%@ page language="java" import="java.util.*,finding.Detail" pageEncoding="gbk"%>
<%@ page  import="java.sql.*"%>
<%@ page import="java.io.*" %>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gbk" />
<title>bbs</title>
<link href="html.css" rel="stylesheet" type="text/css"/>
</head>
 
<body>
<div class="main w">     <div class="header w">-<img src="img/07.jpg" alt="张扬个性" />       
      <div class="menu w">
        <div class="span"><a href="login.jsp">登录</a> |<a href="#"> 注册</a>
         </div> 
      </div>
         </div><!--header end-->
         
         <div class="body1 w" >
         
          <div class="title w" >
             <span class="one" >论坛</span><span class="two" >主题</span><span class="three" >最后发表时间</span>
            </div><!--title end-->             <%
              try{
             Detail board = new Detail();
              board.findIndex();}
              catch(Exception e){
             
              }
              %>
             <%--
              Detail board = new Detail();
              Map result=new HashMap();
              result = board.findIndex();
              for(int i=0;i<result.size();i++){
              --%>     
            <div class="list">
             <div class="borad w"><span><h3><%--=result.get(i) --%></h3></span></div>
                <div class="topic ">
                 <div class="title1"><a href="#">标题</a></div><div class="zt">标题</div><div class="time">标题</div>
                </div><!--topic end-->              
                <div class="topic ">
                 <div class="title1"><a href="#">标题</a></div><div class="zt">标题</div><div class="time">标题</div>
                </div><!--topic end-->               
                <div class="topic ">
                 <div class="title1"><a href="#">标题</a></div><div class="zt">标题</div><div class="time">标题</div>
                </div><!--topic end-->
           
            </div><!--list end-->
     <%--} --%>
                        
         </div><!--body1 end-->
                 
  </div><!--main end-->
  
  <div class="bottom w">madnsee:[email protected]<br/>
  日期：2010-1-21日，晚20：53于宿舍内完成；
  </div>
</body>
</html>