hello!
I was creating a method in a SomethingController.java (actually I rewrote the .create from _Roo_Controller.aj) and when I create a new entity (after executing run mvn tomcat:run) it throws an internal error. This is at the top of the stack trace:

za.co.bsg.rnd.trf.openidlogin.web.EmployeeControll er.create(EmployeeController.java:31)
sun.reflect.NativeMethodAccessorImpl.invoke0(Nativ e Method)

this is EmployeeController.java:

Code:
package za.co.bsg.rnd.trf.openidlogin.web;

import java.io.UnsupportedEncodingException;

import javax.servlet.http.HttpServletRequest;
import javax.validation.Valid;

import org.springframework.roo.addon.web.mvc.controller.RooWebScaffold;
import za.co.bsg.rnd.trf.openidlogin.domain.Employee;

import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.util.UriUtils;
import org.springframework.web.util.WebUtils;
import org.springframework.stereotype.Controller;

@RooWebScaffold(path = "employees", formBackingObject = Employee.class)
@RequestMapping("/employees")
@Controller
public class EmployeeController {
	
	
	@RequestMapping(method = RequestMethod.POST)
    public String create(@Valid Employee employee, BindingResult result, Model model, HttpServletRequest request) {
        if (result.hasErrors()) {
            model.addAttribute("employee", employee);            
            return "employees/create";
        }                
        return "redirect:/employees/" + encodeURLPathSegment(employee.getId().toString(), request); //this is where it throws the error
    }
	
	 @RequestMapping(params = "form2", method = RequestMethod.GET)
	    public String crearForm(Model model) {		 	
	        model.addAttribute("employee", new Employee());
	        return "employees/create";
	    }
	 
	 String encodeURLPathSegment(String pathSegment, HttpServletRequest request) {
	        String enc = request.getCharacterEncoding();
	        if (enc == null) {
	            enc = WebUtils.DEFAULT_CHARACTER_ENCODING;
	        }
	        try {
	            pathSegment = UriUtils.encodePathSegment(pathSegment, enc);
	        }
	        catch (UnsupportedEncodingException uee) {}
	        return pathSegment;
	    }
}
help me please!!
the main question is: what is that native method?