jsp连接mysql数据库时出现错误

当我们在用jsp连接mysql数据库时，出现如下错误时：

SEVERE: Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: Unable to compile class for JSP:

An error occurred at line: 12 in the jsp file: /db.jsp
com.mysql.jdbc.Driver cannot be resolved to a type
9: Statement stmt;
10: ResultSet rs;
11: Class.forName("com.mysql.jdbc.Driver");
12: DriverManager.registerDriver(new com.mysql.jdbc.Driver());
13: String url = "jdbc:mysql://localhost/BookDB?user=root&password=root";
14: con = DriverManager.getConnection(url);
15: stmt = con.createStatement();

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)
Nov 28, 2008 9:58:50 AM org.apache.catalina.startup.HostConfig checkResources

其实就是找不到com.mysql.jdbc.Driver(),故而只要把驱动的jar包放在web服务器的lib目录中，如把mysql-connector-java-5.0.5-bin.jar放在C:/Tomcat 6.0/lib中，或者是在你的web工程目录的WEB-INF/lib下把mysql-connector-java-5.0.5-bin.jar包引入就可以了。。。