eclipse+tomcat5.0 开发jsp连接MYSQL的问题，急！搞了2天了！

myjsp.jsp<%@ page language="java" import="java.util.*,java.sql.*" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>    
    <title>My JSP 'MyJsp.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>
    <%
    String s="h";
    String url="jdbc:mysql://localhost:3306/myweb?user=root&password=adminuser";
    try{
  Class.forName("com.mysql.jdbc.Driver");
  }catch(Exception e)
  {
   out.print("err");
  }
  Connection conn = null;
  try{
  conn = DriverManager.getConnection("jdbc:mysql://localhost/myweb","root","adminuser");
  }catch(SQLException e)
  {
    out.print(e);
  }
  if(conn==null)
  out.print("error");
  out.print("good");
    %>
  </body>
</html>

解决方案 »

  1.   

    提示错误:
    2006-2-21 0:04:53 org.apache.jasper.compiler.Compiler generateClass
    严重: Javac exception 
    Unable to find a javac compiler;
    com.sun.tools.javac.Main is not on the classpath.
    Perhaps JAVA_HOME does not point to the JDK
    at org.apache.tools.ant.taskdefs.compilers.CompilerAdapterFactory.getCompiler(CompilerAdapterFactory.java:106)
    at org.apache.tools.ant.taskdefs.Javac.compile(Javac.java:935)
    at org.apache.tools.ant.taskdefs.Javac.execute(Javac.java:764)
    at org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:382)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:472)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:451)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:439)
    at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:511)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:295)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
    at sun.reflect.GeneratedMethodAccessor61.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:239)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAsPrivileged(Unknown Source)
    at org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:268)
    at org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:157)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
    at org.apache.catalina.core.ApplicationFilterChain.access$000(ApplicationFilterChain.java:50)
    at org.apache.catalina.core.ApplicationFilterChain$1.run(ApplicationFilterChain.java:140)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:136)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:214)
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
    at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:198)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:152)
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137)
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:118)
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
    at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:799)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:705)
    at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:577)
    at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:683)
    at java.lang.Thread.run(Unknown Source)
    2006-2-21 0:04:53 org.apache.jasper.compiler.Compiler generateClass
    严重: Env: Compile: javaFileName=/D:/tomcat5/work/Catalina/localhost/eweb//org/apache/jsp\MyJsp_jsp.java
        classpath=/D:/tomcat5/webapps/eweb/WEB-INF/classes/;/D:/tomcat5/webapps/eweb/WEB-INF/lib/mysql-connector-java-3.1.12-bin.jar;D:\tomcat5\work\Catalina\localhost\eweb;/D:/tomcat5/webapps/eweb/WEB-INF/classes/;/D:/tomcat5/webapps/eweb/WEB-INF/lib/mysql-connector-java-3.1.12-bin.jar;D:/tomcat5/shared/classes/;D:/tomcat5/common/classes/;D:/tomcat5/common/endorsed/xercesImpl.jar;D:/tomcat5/common/endorsed/xml-apis.jar;D:/tomcat5/common/lib/ant-launcher.jar;D:/tomcat5/common/lib/ant.jar;D:/tomcat5/common/lib/commons-collections-3.1.jar;D:/tomcat5/common/lib/commons-dbcp-1.2.1.jar;D:/tomcat5/common/lib/commons-el.jar;D:/tomcat5/common/lib/commons-pool-1.2.jar;D:/tomcat5/common/lib/jasper-compiler.jar;D:/tomcat5/common/lib/jasper-runtime.jar;D:/tomcat5/common/lib/jsp-api.jar;D:/tomcat5/common/lib/naming-common.jar;D:/tomcat5/common/lib/naming-factory.jar;D:/tomcat5/common/lib/naming-java.jar;D:/tomcat5/common/lib/naming-resources.jar;D:/tomcat5/common/lib/servlet-api.jar;/D:/tomcat5/bin/bootstrap.jar;/C:/Program%20Files/Java/j2re1.4.2_04/lib/tools.jar;/C:/Program%20Files/Java/j2re1.4.2_04/lib/ext/dnsns.jar;/C:/Program%20Files/Java/j2re1.4.2_04/lib/ext/ldapsec.jar;/C:/Program%20Files/Java/j2re1.4.2_04/lib/ext/localedata.jar;/C:/Program%20Files/Java/j2re1.4.2_04/lib/ext/sunjce_provider.jar
        cp=D:\tomcat5\bin\bootstrap.jar;C:\Program Files\Java\j2re1.4.2_04\lib\tools.jar
        cp=D:\tomcat5\webapps\eweb\WEB-INF\classes
        cp=D:\tomcat5\webapps\eweb\WEB-INF\lib\mysql-connector-java-3.1.12-bin.jar
        cp=D:\tomcat5\work\Catalina\localhost\eweb
        cp=D:\tomcat5\webapps\eweb\WEB-INF\classes
        cp=D:\tomcat5\webapps\eweb\WEB-INF\lib\mysql-connector-java-3.1.12-bin.jar
        cp=D:\tomcat5\shared\classes
        cp=D:\tomcat5\common\classes
        cp=D:\tomcat5\common\endorsed\xercesImpl.jar
        cp=D:\tomcat5\common\endorsed\xml-apis.jar
        cp=D:\tomcat5\common\lib\ant-launcher.jar
        cp=D:\tomcat5\common\lib\ant.jar
        cp=D:\tomcat5\common\lib\commons-collections-3.1.jar
        cp=D:\tomcat5\common\lib\commons-dbcp-1.2.1.jar
        cp=D:\tomcat5\common\lib\commons-el.jar
        cp=D:\tomcat5\common\lib\commons-pool-1.2.jar
        cp=D:\tomcat5\common\lib\jasper-compiler.jar
        cp=D:\tomcat5\common\lib\jasper-runtime.jar
        cp=D:\tomcat5\common\lib\jsp-api.jar
        cp=D:\tomcat5\common\lib\naming-common.jar
        cp=D:\tomcat5\common\lib\naming-factory.jar
        cp=D:\tomcat5\common\lib\naming-java.jar
        cp=D:\tomcat5\common\lib\naming-resources.jar
        cp=D:\tomcat5\common\lib\servlet-api.jar
        cp=D:\tomcat5\bin\bootstrap.jar
        cp=C:\Program%20Files\Java\j2re1.4.2_04\lib\tools.jar
        cp=C:\Program%20Files\Java\j2re1.4.2_04\lib\ext\dnsns.jar
        cp=C:\Program%20Files\Java\j2re1.4.2_04\lib\ext\ldapsec.jar
        cp=C:\Program%20Files\Java\j2re1.4.2_04\lib\ext\localedata.jar
        cp=C:\Program%20Files\Java\j2re1.4.2_04\lib\ext\sunjce_provider.jar
        work dir=D:\tomcat5\work\Catalina\localhost\eweb
        extension dir=C:\Program Files\Java\j2re1.4.2_04\lib\ext
        srcDir=D:\tomcat5\work\Catalina\localhost\eweb
        include=org/apache/jsp/MyJsp_jsp.java2006-2-21 0:04:53 org.apache.jasper.compiler.Compiler generateClass
    严重: Error compiling file: /D:/tomcat5/work/Catalina/localhost/eweb//org/apache/jsp\MyJsp_jsp.java     [javac] Compiling 1 source file
      

  2.   

    conn = DriverManager.getConnection("jdbc:mysql://localhost/myweb","root","adminuser");
    主要是这句的问题，但不知道问题在那！
      

  3.   

    倒，楼主，提示说是找不到编译器类，因此你的应用服务器应该不能够正确处理任何一个 JSP 文件才对，与具体的代码没有关系吧。
      

  4.   


    servlet+javabean实现方法：servlet 部门:import java.io.IOException;
    import java.io.PrintWriter;import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    /*
     * 创建日期 2006-2-20
     *
     * TODO 要更改此生成的文件的模板，请转至
     * 窗口 － 首选项 － Java － 代码样式 － 代码模板
     *//**
     * @author IBM
     *
     * TODO 要更改此生成的类型注释的模板，请转至
     * 窗口 － 首选项 － Java － 代码样式 － 代码模板
     */
    public class Hi extends HttpServlet { /**
     * Constructor of the object.
     */
    public Hi() {
    super();
    } /**
     * Destruction of the servlet. <br>
     */
    public void destroy() {
    super.destroy(); // Just puts "destroy" string in log
    // Put your code here
    } /**
     * The doGet method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to get.
     * 
     * @param request the request send by the client to the server
     * @param response the response send by the server to the client
     * @throws ServletException if an error occurred
     * @throws IOException if an error occurred
     */
    public void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException { response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    out
    .println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
    out.println("<HTML>");
    out.println("  <HEAD><TITLE>A Servlet</TITLE></HEAD>");
    out.println("  <BODY>");
    if(mysql.getConnection()==null)
    {
    out.print("error");
    }else
    {
       out.print("good");
    }
    out.print("    This is ");
    out.print(this.getClass());
    out.println(", using the GET method");
    out.println("  </BODY>");
    out.println("</HTML>");
    out.flush();
    out.close();
    } /**
     * The doPost method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to post.
     * 
     * @param request the request send by the client to the server
     * @param response the response send by the server to the client
     * @throws ServletException if an error occurred
     * @throws IOException if an error occurred
     */
    public void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException { response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    out
    .println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
    out.println("<HTML>");
    out.println("  <HEAD><TITLE>A Servlet</TITLE></HEAD>");
    out.println("  <BODY>");
    out.print("    This is ");
    out.print(this.getClass());
    out.println(", using the POST method");
    out.println("  </BODY>");
    out.println("</HTML>");
    out.flush();
    out.close();
    } /**
     * Initialization of the servlet. <br>
     *
     * @throws ServletException if an error occure
     */
    public void init() throws ServletException {
    // Put your code here
    }}
      

  5.   


    mysql类public class mysql { public static Connection getConnection()
    {
     try{
        Class.forName("com.mysql.jdbc.Driver").newInstance(); 
        }catch(Exception e)
        {
         //com.mysql.jdbc.driver"
         System.out.print("driver");
        }
        Connection conn = null;
        try{
        conn = DriverManager.getConnection("jdbc:mysql://localhost/myweb","root","adminuser");
        
        }catch(SQLException e)
        {
          System.out.print("jdbc:mysql://localhost/myweb");
        }
    return conn;
    }
    }
      

  6.   

    设置 JAVA_HOME 环境变量到你的 JDK 安装目录，再用 conn = DriverManager.getConnection(url); 试试，你的代码中已经定义了 url 却未使用。
      

  7.   

    控制台的信息为：
    jdbc:mysql://localhost/myweb
    说明：
    conn = DriverManager.getConnection("jdbc:mysql://localhost/myweb","root","adminuser");
    出错，但错在那里啊？
      

  8.   

    JAVA_HOME
    已经设置好了的啊：
    C:\j2sdk1.4.2_04ecpise使用是3。0
    tomcat5.0
      

  9.   

    CLASSPATHC:\j2sdk1.4.2_04\lib\tools.jar;C:\j2sdk1.4.2_04\lib\dt.jar;.
      

  10.   

    conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/myweb","root","adminuser");
      

  11.   

    C:\j2sdk1.4.2_04\lib\dt.jar
    起什么做用,只有这个没有测试了。!
      

  12.   

    com.sun.tools.javac.Main is not on the classpath.
    Perhaps JAVA_HOME does not point to the JDK
    是环境变量的问题
      

  13.   

    conn = DriverManager.getConnection("jdbc:mysql://localhost/myweb","root","adminuser");(错误）conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/myweb","root","adminuser");（正确）你没有写端口号，就是那个“3306”
      

  14.   

    如果是JDK的错误的话,为什么一般的JSP不会出错呢?!加了数据库的就会出错?!