Erro servlet

type Status report

message Servlet Banco is currently unavailable

description The requested service (Servlet Banco is currently unavailable) is not currently available.

type Exception report

message 

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

exception 

javax.servlet.ServletException: Class br.com.ctis.Banco is not a Servlet
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root cause 

java.lang.ClassCastException
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<form action="banco" method="POST" >

public class Banco
{
     public void doPost(HttpServletRequest request, HttpServletResponse response) 	   throws IOException, ServletException
        {
         String nome = request.getParameter("nome"); 
         String email = request.getParameter("email");
         String user = request.getParameter("user");
         String password = request.getParameter("password");
		 		
         Conectar.inserir(nome, email, user, password);
       
       
         response.sendRedirect("http://localhost:8080/Leo/cadastroOK.jsp");
         }
}

public class Conectar 
{ 
	public static Connection getConnection() 
	  {
		try
		 {
		   Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
		   return DriverManager.getConnection("jdbc:odbc:Banco","1234","1234");
		 }
		  catch (ClassNotFoundException e)
		   {
		   System.out.println("Conectar-ClassNotFoundException");
		   } 
			  
		  catch (SQLException e1)
		   {
			System.out.println("Conectar-SQLException");
		   }
			
	  return null;
	  }
	  
	static void inserir(String nome, String email, String user, String password)
		{
			try
			{
			Connection con = Conectar.getConnection();
			Statement stat = con.createStatement();
			stat.executeUpdate("INSERT INTO Teste(nome,mail, user, password) VALUES ('" + nome + "', '" + email + "','" + user + "', '" + password + "')");
		
			stat.close();
			con.close();
			}
				catch(Exception e)
				{	
				  System.out.println("Erro no comando de SQL INSERT: " + e.toString());
				}
			
		}
	  
	  
}