Cadastro usuário

Boa a tarde, durante o curso foi feito o cadastro de um usuário direto no banco de dados e tambem a definição da role desse usuario, então fiquei curioso e resolvi desenvolver um cadastro de usuario onde fosse possivel atravez de um radio button definir quais roles teria os usuarios. quando tento acessar meu formulario de cadastro (/usuarios/form/cadastro) recebo:

org.springframework.beans.NotReadablePropertyExceptionInvalid property 'roles.previlegio' of bean class [br.com.clienteoculto.models.Usuario]: Bean property 'roles.previlegio' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?

eu já refiz meus getter e setter mas da clase Role mais ainda assim recebo a exception

segue minha classe Usuario

package br.com.clienteoculto.models;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.ManyToMany;

import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.userdetails.UserDetails;

@Entity
public class Usuario implements UserDetails {

    private static final long serialVersionUID = 1L;

    @Id
    private String email;
    private String senha;
    private String nome;
    @ManyToMany(fetch=FetchType.EAGER)
    private List <Role> roles = new ArrayList<Role>() ;

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getSenha() {
        return senha;
    }

    public void setSenha(String senha) {
        this.senha = senha;
    }

    public String getNome() {
        return nome;
    }

    public void setNome(String nome) {
        this.nome = nome;
    }

    public List<Role> getRoles() {
        return roles;
    }

    public void setRoles(List<Role> roles) {
        this.roles = roles;
    }

    @Override
    public Collection<? extends GrantedAuthority> getAuthorities() {
        return roles;
    }

    @Override
    public String getPassword() {
        return senha;
    }

    @Override
    public String getUsername() {
        return email;
    }

    @Override
    public boolean isAccountNonExpired() {
        return true;
    }

    @Override
    public boolean isAccountNonLocked() {
        return true;
    }

    @Override
    public boolean isCredentialsNonExpired() {
        return true;
    }

    @Override
    public boolean isEnabled() {
        return true;
    }    
}

segue a classe UsuarioDAO

package br.com.clienteoculto.daos;

import java.util.List;

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.stereotype.Repository;

import br.com.clienteoculto.models.Usuario;

@Repository
public class UsuarioDAO implements UserDetailsService{

    @PersistenceContext
    private EntityManager manager;

    @Override
    public UserDetails loadUserByUsername (String email) throws UsernameNotFoundException {
        String jpql = "select u from Usuario u where u.email = :email";    
        List<Usuario> usuarios    = manager.createQuery(jpql, Usuario.class)
                .setParameter("email", email).getResultList();

     if(usuarios.isEmpty()){
         throw new UsernameNotFoundException("o " + email + " não foi encontrado!");
     }

     return usuarios.get(0);
    }

    public void adicionaUsuario(Usuario usuario){
        BCryptPasswordEncoder passwordEncoder = new BCryptPasswordEncoder();
        String hasSenha = passwordEncoder.encode(usuario.getSenha());
        usuario.setSenha(hasSenha);        
        manager.persist(usuario);
        }

    public List<Usuario> lista() {
        return manager.createQuery("select u from Usuario u", Usuario.class).getResultList();
    }


}

segue classe UsuariosController

package br.com.clienteoculto.controllers;

import java.util.List;

import javax.validation.Valid;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.support.RedirectAttributes;

import br.com.clienteoculto.daos.UsuarioDAO;
import br.com.clienteoculto.models.Usuario;

@Controller
@RequestMapping("/usuarios")
public class UsuariosController {

    @Autowired
    private UsuarioDAO usuarioDAO;

    @RequestMapping(method=RequestMethod.POST)
    public ModelAndView grava(@Valid Usuario usuario, BindingResult result,
                                RedirectAttributes redirectAttributes ){
        if(result.hasErrors()){
            return form(usuario);
        }
        usuarioDAO.adicionaUsuario(usuario);
        redirectAttributes.addFlashAttribute("sucesso", "Usuario "+usuario+" cadastrado com sucesso!");

        return new ModelAndView("redirect:usuarios");
    }

    @RequestMapping("/form/cadastro")
    public ModelAndView form(Usuario usuario) {
        ModelAndView modelAndView = new ModelAndView("usuarios/form-cad-usuario");
        return modelAndView;
    }

    @RequestMapping(method=RequestMethod.GET)
    public ModelAndView lista(){
        List<Usuario> usuarios = usuarioDAO.lista();
        ModelAndView modelAndView = new ModelAndView("usuarios/lista-usuario");
        modelAndView.addObject("usuarios", usuarios);

        return modelAndView;
    }

}

Por fim a jsp

package br.com.clienteoculto.controllers;

import java.util.List;

import javax.validation.Valid;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.support.RedirectAttributes;

import br.com.clienteoculto.daos.UsuarioDAO;
import br.com.clienteoculto.models.Usuario;

@Controller
@RequestMapping("/usuarios")
public class UsuariosController {

    @Autowired
    private UsuarioDAO usuarioDAO;

    @RequestMapping(method=RequestMethod.POST)
    public ModelAndView grava(@Valid Usuario usuario, BindingResult result,
                                RedirectAttributes redirectAttributes ){
        if(result.hasErrors()){
            return form(usuario);
        }
        usuarioDAO.adicionaUsuario(usuario);
        redirectAttributes.addFlashAttribute("sucesso", "Usuario "+usuario+" cadastrado com sucesso!");

        return new ModelAndView("redirect:usuarios");
    }

    @RequestMapping("/form/cadastro")
    public ModelAndView form(Usuario usuario) {
        ModelAndView modelAndView = new ModelAndView("usuarios/form-cad-usuario");
        return modelAndView;
    }

    @RequestMapping(method=RequestMethod.GET)
    public ModelAndView lista(){
        List<Usuario> usuarios = usuarioDAO.lista();
        ModelAndView modelAndView = new ModelAndView("usuarios/lista-usuario");
        modelAndView.addObject("usuarios", usuarios);

        return modelAndView;
    }

}

desde já obrigado!