java ejb加了一个service层后在web层调用sessionBean报空指针

在FirstAppEJB里面的有：package com.ejb.service.impl;import java.util.List;import javax.ejb.Remote;
import javax.ejb.Stateful;import com.ejb.beans.Employee;
import com.ejb.dao.EmployeeDao;
import com.ejb.service.EmployeeService;
@Stateful
@Remote(EmployeeService.class)
public  class EmployeeServiceBean implements EmployeeService {

private EmployeeDao employeeDao;
public void setEmployeeDao(EmployeeDao employeeDao) {
this.employeeDao = employeeDao;
}
public Employee find(String id) {
return employeeDao.find(id);
}
public void add(Employee employee) {
employeeDao.add(employee);
}
public void remove(Employee employee) {
employeeDao.remove(employee);
}
public List<Employee> findAll() {
return employeeDao.findAll();
}
public List<Employee> findPages(int pageNow, int pageSize) {
return employeeDao.findPages(pageNow, pageSize);
}
public int findPageSize() {
return employeeDao.findPageSize();
}
}在web层调用的有：
package com.web.action.Action;import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;import com.ejb.beans.Employee;
import com.ejb.dao.EmployeeDao;
import com.ejb.page.Pager;
import com.ejb.service.EmployeeService;
import com.web.action.Form.EmployeeForm;
import com.web.action.service.ServiceTool;public class FindAllEmployeeAction extends Action {
//  private static EmployeeDao employeeDao;
    private static EmployeeService employeeDao;
private final static int PAGE_SIZE=3; public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
     
    EmployeeForm employeeForm = (EmployeeForm) form;
//      EmployeeDao employeeDao = (EmployeeDao)EJBFactory.getEJB("FirstAppVelocity/EmployeeDaoBean/remote");
    EmployeeService employeeDao=(EmployeeService)EJBFactory.getEJB("FirstAppVelocity/EmployeeServiceBean/remote");      
      int pageNow = 1;
      String  pageNowStr = request.getParameter("pageNow");
 
 if(pageNowStr!=null && !"".equals(pageNowStr)){
 pageNow = Integer.parseInt(pageNowStr);
 }
  
  
 int totalSize=employeeDao.findPageSize();

List<Employee> employeeList1=employeeDao.findPages(pageNow,this.PAGE_SIZE);
request.setAttribute("employeeList1", employeeList1);
Pager page=new Pager(pageNow,totalSize);
request.setAttribute("page", page);

return mapping.findForward("success");
   }
}报错误为：空指针，获取不到employeeDao.findPageSize()也就是远程调用不了求指点javawebejbexception