帮我看看这代码哪错了

[q5661889]

<%@ page language="java" import="java.sql.*" pageEncoding="GB2312"%>
连接MySQL数据库<br>
<%
String driverClass="com.mysql.jdbc.Driver";
String url="jdbc:mysql://localhost:3306/mysql";
String username="root";
String password="";
Class.forName(driverClass);//加载数据库驱动
Connection conn=DriverManager.getConnection(url,username,password); //建立连接
Statement stmt=conn.createStatement();
int rnt = stmt.executeUpdate("insert into db (Host,Db) value('123','456')");
ResultSet rs =stmt.executeQuery("select * from db"); //执行SQL语句
while(rs.next()){
out.println("<br>用户名:"+rs.getString(1)+"密码:"+rs.getString(2));
}
%>
这段代码我在A项目里建个jsp文件，然后把代码复制进去，能运行，但是我在B项目里就不能运行，这可能是什么原因？

[Atest001]

人品时好时坏？
请贴上错误信息。

[q5661889]

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: An exception occurred processing JSP page /MyJsp.jsp at line 8

5: String url="jdbc:mysql://localhost:3306/mysql";
6: String username="root";
7: String password="";
8: Class.forName(driverClass);//加载数据库驱动
9: Connection conn=DriverManager.getConnection(url,username,password); //建立连接
10: Statement stmt=conn.createStatement();
11: int rnt = stmt.executeUpdate("insert into db (Host,Db) value('1333','456')");


Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:519)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:410)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


root cause

javax.servlet.ServletException: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:865)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:794)
org.apache.jsp.MyJsp_jsp._jspService(MyJsp_jsp.java:77)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:386)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


root cause

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526)
org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:128)
org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:66)
java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
java.lang.Class.forName0(Native Method)
java.lang.Class.forName(Class.java:164)
org.apache.jsp.MyJsp_jsp._jspService(MyJsp_jsp.java:61)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:386)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


note The full stack trace of the root cause is available in the Apache Tomcat/6.0.32 logs.

[zn85600301]

驱动jar包都没有~~

[axie534]

呵呵 是不是你的驱动包忘记了啊

[Atest001]

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver

Jar包没找到啊。

[幽饮烛]

com.mysql.jdbc.Driver

B 项目没有驱动包

[大河V5]

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver

在B项目中也把驱动包加进去。

[miracleliu]

没有驱动包。。。

[JavaMan_KA]

你的B项目中没有 数据库的jar包
你把jar包考到B项目的WEB-INF/lib中，重新启动就可以了

[jilongliang]

没有找到驱动...请你加入Mysql驱动...lib文件目录下