求大神指导！尝试MVC模式时出错

求大神指点！尝试MVC模式时出错
求大神帮忙看下在哪里有错，谢谢！
网站项目名为ch1；

JavaBean是User类，包含username,password,sex三个属性，在ch1/scr目录下的com.henu.bean包中；
RegisterAction.java在src目录下的com.henu.servic包中

register.jsp页面中部分代码：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8" import="java.sql.*"%>
    <jsp:useBean id="UsersBean" class="com.henu.bean.Users"></jsp:useBean>
<jsp:setProperty property="*" name="UserBean"/>
<form action="/ch1/RegisterAction" name="RegisterForm" method="post">
	用户名：<input type="text" name="username"><br>
	性别：男<input type="radio" name="sex">女<input type="radio" name="sex"><br>
	密码：<input type="password" name="password"><br>
	<input type="submit" value="提交">
	<input type="reset" value="重置">
</form>

报错主要是在RegisterAction
exception 

javax.servlet.ServletException: Error instantiating servlet class servlet.RegisterAction
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
java.lang.Thread.run(Unknown Source)


root cause 

java.lang.ClassNotFoundException: servlet.RegisterAction
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
java.lang.Thread.run(Unknown Source)


下面是RegisterAction.java

package com.henu.service;

import java.io.IOException;
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;
//import java.text.SimpleDateFormat;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.henu.bean.Users;
import com.henu.util.DbConnection;

public class RegisterAction extends HttpServlet
{
	private static final long serialVersionUID = 1L;
	public RegisterAction()
	{
		super();
	}
	
	@Override
	protected void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException
	{
		Users regUsers = new Users();//JavaBean
		
//		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
		
		regUsers.setUsername(request.getParameter("username"));
		regUsers.setSex(request.getParameter("sex"));
		regUsers.setPassword(request.getParameter("password"));
		
		String sql = "INSERT INTO 'zcbtext'.'users' (username,sex,password)VALUES ('" + regUsers.getUsername() + "','" + regUsers.getSex() + "','" + regUsers.getPassword() + "')";
		
		try
		{
			Connection con = DbConnection.getConn();//连接数据库
			Statement stmt = con.createStatement();//执行给定的sql语言insert,update,delete
			stmt.executeUpdate(sql);
//			response.sendRedirect("pages/confirmRegister.jsp");
			con.close();
		}
		catch(SQLException e)
		{
			e.printStackTrace();
		}
		HttpSession session = request.getSession(true);
		session.setAttribute("users",regUsers);
		
	}
	@Override
	protected void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException
	{
		doGet(request,response);
	}
}

web.xml中已经配置好servlet

<servlet>