我是Java Web Development的新手,最近我開始了一門課程,我有一個任務來連接到MySQL數據庫並顯示它。我有Eclipse Kepler和Java 7.55,而我的服務器是GlassFish 4.0和MySQL 6.0.9。我已將jdbc連接器添加到項目(WEB-INF/lib)中,並且還具有JRE系統庫和Web App庫的連接器。JDBC連接器 - Java EE - Eclipse開普勒 - ClassNotFoundException
我有另一個動態的網站項目,我用文件上傳和那裏我能夠添加不同的外部jar文件,如上所述,它一切正常。 我對以下問題做了同樣的處理,但仍然出現錯誤。 我也嘗試重新安裝Eclipse和服務器和MySQL jdbc連接器,但沒有任何幫助。我刪除了該項目並重新構建它,但仍然沒有任何結果。
jdbc連接器添加到每個庫中的任何位置,我都可以考慮添加它。
我創建了一個新的項目,所以我能夠連接到MySQL數據庫
但是,當我運行下面的代碼(從.jsp文件),我得到的錯誤:
> HTTP Status 500 - Internal Server Error
>
> --------------------------------------------------------------------------------
>
> type Exception report
>
> messageInternal Server Error
>
> description The server encountered an internal error that prevented it from fulfilling this request.
>
> exception
> javax.servlet.ServletException: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
>
> root cause
> java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
>
And in the console I get this description:
*2014-05-13T21:12:13.195+0300|Warning: StandardWrapperValve[jsp]: Servlet.service() for servlet jsp threw exception
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at org.glassfish.web.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1761)
at org.glassfish.web.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1611)
at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:187)
at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:125)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:190)
at org.apache.jsp.index_jsp._jspService(index_jsp.java:52)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:411)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:473)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:377)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188)
at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191)
at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168)
at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189)
at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114)
at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838)
at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544)
at java.lang.Thread.run(Thread.java:744)*
這個.jsp代碼:
<%@page import="java.sql.Connection"%>
<%@page import="java.sql.DriverManager"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/users", "root", "emperor05");
%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page - Database Connection</title>
</head>
<body>
<h2>Database Connection</h2>
</body>
</html>
如果對不起這是一個問題的重新發布,但我沒能找到正確的答案?
幫助?
預先感謝您。
嘗試將該JAR放入Glassfish服務器/ lib而不是您的項目WEB-INF/lib。也許Java EE類加載器需要先看到它才能創建池。 – duffymo
你的回答幫了我。 @duffymo。你知道如何將你的評論標記爲可接受的答案嗎? – Tanata05
不,不可能。你只能接受答案。如果你願意,我會做出答案。 – duffymo