为什么我得到这个[ClassNotFoundException com.mysql.jdbc.Driver]？

Question

通过JSP将数据推送到我的数据库给我ClassNotFoundException，而从main方法解析数据工作得很好。

我有我的mysql-connector jar和一切就绪，

在下面的类中，几乎没有打开/关闭数据库连接的方法。

package com.socialhub.dao;

import java.sql.Connection;
import java.sql.DriverManager;

public class DBConnection {
    public static int client = 0;

    public static Connection getConnection() {
        Connection con = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            con = DriverManager.getConnection("jdbc:mysql://localhost:3306/socialhub","root","root");
            client++;
        } catch (Exception e) {
            System.out.println("Connection issue " + e.getMessage());
            e.printStackTrace();
        }
        return con;
    }
    public void closeConnection(Connection conn) {
        try {
            conn.close();
            client--;
        } catch (Exception e) {
            System.out.println("Connection Close Issue" + e.getMessage());
        }
    }
    public int getClient() {
        return client;
    }
}

<%@ page import="com.socialhub.action.Service"%>  
<% 
String username=request.getParameter("uname");
String fullname=request.getParameter("fname");
String password=request.getParameter("password");
String country=request.getParameter("country");
String gender=request.getParameter("gender");

Service service=new Service();
String message="";
int valid=0;
try {
	country.length();
}
catch(Exception e) {
	country="na";
}
if(country.equalsIgnoreCase("na")||country.equalsIgnoreCase("null")||country==null) {
	message="Invalid Username and Password";
	valid=service.checkcredential(username,password);
	if(valid==0) {
		response.sendRedirect("profile.jsp");
	} else {
    	response.sendRedirect("login.jsp?message="+message);
	}
}
else {
	valid=service.save(fullname, country, gender, username, password);
	if(valid==1) {
		message="Registration Successfully completed";
		response.sendRedirect("login.jsp?message="+message); 
	}
	else {
		message="Some Server Error";
		response.sendRedirect("login.jsp?message="+message); 
	}
}
%>