连接数据库问题

Question

我用jsp连接数据库，代码如下：
Class.forName("com.mysql.jdbc.Driver").newInstance();
String url="jdbc:mysql://localhost/mydb";
Connection con = DriverManager.getConnection(url,"1","1"); 抛出异常
javax.servlet.ServletException: com.mysql.jdbc.Driver
at org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:457)
at org.apache.jsp.loginPost$jsp._jspService(loginPost$jsp.java:126)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:107)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:202)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:382)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:474)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:201)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:246)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2344)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:170)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:170)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:462)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:163)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:1011)
at org.apache.catalina.connector.http.HttpProcessor.run(HttpProcessor.java:1106)
at java.lang.Thread.run(Thread.java:595)请问是怎么回事？

Answer 1

你的驱动装载有问题把
String url="jdbc:mysql://localhost/mydb";
起码有个端口号3306把
String url="jdbc:mysql://localhost:3306/mydb";

Answer 2

Class.forName("com.mysql.jdbc.Driver").newInstance();
String url ="jdbc:mysql://localhost/mydb?user=longying&password=ly123&useUnicode=true&characterEncoding=gb2312";
Connection mobjConn = DriverManager.getConnection(url);  
Statement mobjState = mobjConn.createStatement();
这是完整的连接MYSQL的代码
还有你把驱动放在LIB下了吗？

Answer 3

我下载了mysql-connector-java-bin.jar后，请问要如何配置？
我用的是tomcat4.0和apache

Answer 4

把mysql-connector-java-bin.jar放到TOMCAT目录下的common\lib目录下就行了

Answer 5

tomcat4有点老了
检查驱动放的地方对不?
实在不行自己在这里搜一下,问这个问题的人很多哦

Answer 6

我已经把mysql-connector-java-bin.jar放到TOMCAT目录下的common\lib目录下了，可还是报同样的错误。感觉还是没有起作用。

Answer 7

1.将jar包放到tomcat目录下问题应该可以解决2.如果还是不行..
把tomcat重装下看看..

Answer 8

驱动的jar包放到工程的lib下，或者tomcat的common\lib下