求搭救，使用Servlet的时候Tomcat老是要重启差不多3次才能看到数据表，怎么办

Question

servlettomcat数据

Answer 1

贴代码，贴tomcat错误日志，贴tomcat配置文件，给大家看看

Answer 2

O.O09-May-2014 00:02:15.379 SEVERE [http-apr-8080-exec-9] org.apache.catalina.core.StandardWrapperValve.invoke Servlet.service() for servlet [jsp] in context with path [] threw exception [javax.servlet.ServletException: java.lang.NoClassDefFoundError: book/book] with root cause
 java.lang.ClassNotFoundException: book.book
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1284)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1132)
at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:125)
at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:62)
at org.apache.jsp.页面_jsp._jspService(页面_jsp.java:79)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:403)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:347)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:301)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:136)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:74)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:516)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1015)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:652)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:277)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2451)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2440)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:722)09-May-2014 00:57:45.626 INFO [localhost-startStop-2] org.apache.catalina.core.ApplicationContext.log SessionListener: contextDestroyed()
09-May-2014 00:57:45.626 INFO [localhost-startStop-2] org.apache.catalina.core.ApplicationContext.log ContextListener: contextDestroyed()
09-May-2014 08:06:29.564 INFO [localhost-startStop-1] org.apache.catalina.core.ApplicationContext.log ContextListener: contextInitialized()
09-May-2014 08:06:29.564 INFO [localhost-startStop-1] org.apache.catalina.core.ApplicationContext.log SessionListener: contextInitialized()
09-May-2014 10:37:48.950 INFO [localhost-startStop-2] org.apache.catalina.core.ApplicationContext.log SessionListener: contextDestroyed()

Answer 3

额..你的页面是中文的么,另外.你的book这个类在页面有没有import

Answer 4

贴一下这边的代码，这是book.java的
package chongxieServlet;import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;/**
 *
 * @author Administrator
 */
public class book 
   extends HttpServlet {
    private static final String CONTENT_TYPE = "text/html; charset=GB2312";
    private Connection con;
    private Statement stmt;
    private ResultSet rs;
    
   
    public void init(ServletConfig config) throws ServletException {
        super.init(config);
    }
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException 
    {
        response.setContentType(CONTENT_TYPE);
        PrintWriter out=response.getWriter();
        
        out.print("<HTML>");
        out.print("<BODY>");
        
        String bookid=request.getParameter("bookid");
        out.println(bookid);
        String bookname=request.getParameter("bookname");
        out.println(bookname);
        String writer=request.getParameter("writer");
        out.println(writer);
        String publish=request.getParameter("publish");
        out.println(publish);
        try{
            Class.forName("sun.jdbc.odbc.JdbcDriver");
        }catch(ClassNotFoundException e){e.printStackTrace();}
        try{
            con=DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql","root","ydx");
            stmt=con.createStatement();
            String sql="Select * from biao where bookid like \"+\"'\"+bookid+\"'";
            rs=stmt.executeQuery(sql);
            out.print("<Table Border>");
            out.print("<TR>");
            out.print("<TH width=100>"+"bookid");
            out.print("<TH width=100>"+"bookname");
            out.print("<TH widtn=50>"+"writer");
            out.print("<TH width=50>"+"publish");
            out.print("</TR>");
            
            while(rs.next())
            {
                out.print("<TR>");
                bookid=rs.getString("bookid");
                out.print("<TD>"+bookid+"</TD>");
                bookname=rs.getString("bookname");
                out.print("<TD>"+bookname+"</TD>");
                writer=rs.getString("writer");
                out.print("<TD>"+writer+"</TD>");
                publish=rs.getString("publish");
                out.print("<TD>"+publish+"</TD>");
                out.print("</TR>");
            }
            out.print("</Table>");
            con.close();
        }catch(SQLException e)
        {}
        out.println("</BODY>");
        out.println("</HTML>");
    }
    @Override
    public void destroy() {
        
    }}下面是 页面.jsp的<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB2312"><title>T^T </title>
</head>
<body>
<center>
 
<h2>T^T~5555~</h2><%@ page language="java" import="java.sql.*" %>
 
<jsp:useBean id="user" scope="page" class="book.book" />
<% user.init();
%>
<br><br>
<table border="1" align="center">
<tr><th>Number</th><th>Bookname</th><th>writer</th><th>publisher</th></tr>
 
<%
ResultSet RS = user.executeQuery("SELECT * FROM biao");
while (RS.next()) {
 out.print("<tr>");
   out.print("<td>"+RS.getString("bookid")+"</td>");       
   out.print("<td>"+RS.getString("bookname")+"</td>");   
   out.print("<td>"+RS.getString("writer")+"</td>");    
   out.print("<td>"+RS.getString("publish")+"</td>");   
   out.print("</tr>");
}  
RS.close();
%>
 
</table>
<% user.close(); %>
</center>
</body>
</html>

Answer 5

同志，在JSP里面写Java代码在企业里是不被允许的哦，考虑JSTL语句吧

Answer 6

Connection,Resultset 用完记得调用close()方法 , .的close方法,建议放到  finally 块内执行.  
还有就是 俺没有从 book.java里看到executeQuery和close()方法, 难道是你从哪里复制的代码.?

Answer 7

我说lz绝对牛X，jsp页面直接操作数据库！！！