Custom Realm for dinamic roles

MyRealm

import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.AuthenticationInfo;
import org.apache.shiro.authc.AuthenticationToken;
import org.apache.shiro.authc.SimpleAuthenticationInfo;
import org.apache.shiro.authc.UsernamePasswordToken;
import org.apache.shiro.authz.AuthorizationException;
import org.apache.shiro.authz.AuthorizationInfo;
import org.apache.shiro.authz.SimpleAuthorizationInfo;
import org.apache.shiro.realm.AuthorizingRealm;
import org.apache.shiro.subject.PrincipalCollection;

import com.google.inject.Inject;
import com.rhem.server.dao.PersonalUserDao;
import com.rhem.server.domain.PersonalUser;
import com.rhem.server.domain.Role;
import com.rhem.server.domain.RoleUser;
import com.rhem.server.util.PasswordEncryptionService;

//http://shiro-user.582556.n2.nabble.com/How-to-add-a-role-to-the-subject-td5562700.html
public class MyRealm extends AuthorizingRealm{

        @Inject PersonalUserDao udao;
        @Inject PasswordEncryptionService pes;
        
        /**
        this function loads user authorization data from "userManager" data source (database)
        User, Role are custom POJOs (beans) and are loaded from database.  
        WildcardPermission implements shiros Permission interface, so my permissions in database gets accepted by shiro sigmac
        **/
        @Override
        protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principals) {
                Set<String> roles = new HashSet<String>();
                Set<String> permissions = new HashSet<String>();
                Collection<String> principalsList = principals.byType(String.class);
                
                if (principalsList.isEmpty()) {
                        throw new AuthorizationException("Empty principals list!");
                }

                //LOADING STUFF FOR PRINCIPAL
                for (String username : principalsList) {
                        PersonalUser user = udao.getPersonalUser(username);
                        List<RoleUser> userRoles = udao.getRoles(user);
                        for(RoleUser userRol : userRoles){
                                Role rol = userRol.getRole();
                                roles.add(rol.getName());
                                List<String> userPermissions = udao.getPermissions(rol);
                                for(String permission : userPermissions){
                                   if (!permissions.contains(permission)) {
                                		 permissions.add(permission);
                                	 }
                                }                                
                        }
                         
                }
                
                SimpleAuthorizationInfo info = new SimpleAuthorizationInfo(roles);      
                info.setRoles(roles); //fill in roles 
                info.setStringPermissions(permissions);
                return info;
        }

        @Override
        protected AuthenticationInfo doGetAuthenticationInfo(
                        AuthenticationToken token) throws AuthenticationException {
                UsernamePasswordToken upToken = (UsernamePasswordToken) token;
                if (upToken.getUsername() == null || upToken.getUsername().isEmpty()) {
                        throw new AuthenticationException("Authentication failed");
                }
                String username = upToken.getUsername();
                String password = String.valueOf(upToken.getPassword());
                
                PersonalUser user = udao.getPersonalUser(username);
                if(user == null)
                        throw new AuthenticationException("Authentication failed");
                
                byte[] encryptedPassword = user.getPassword();
                byte[] salt = user.getSalt();
                
                try {
                        if(!pes.authenticate(password, encryptedPassword, salt)){
                                throw new AuthenticationException("Authentication failed");
                        }
                } catch (NoSuchAlgorithmException e) {
                        e.printStackTrace();
                } catch (InvalidKeySpecException e) {
                        e.printStackTrace();
                }
                
                
                return new SimpleAuthenticationInfo(username, password, getName());
        }

}