Java开发之spring security实现基于MongoDB的认证功能

public class CustomUserDetailsService implements UserDetailsService {  @Autowired  MongoDBHelper dbhelper;    @Override  public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {     //步骤一:从数据库中查出用户数据    MongoDatabase db = dbhelper.getDB("huanle");    MongoCollection<Document> users = db.getCollection("user");    Document filter = new Document();    filter.append("account",username);    Document result = users.find(filter).first();    if(result==null) throw new UsernameNotFoundException(username+"不存在");    //步骤二:装配到UserDetails，相当于生成了一个<user>标签    UserDetails userDetails = new User(result.getString("account"),           result.getString("password"), true, true, true, true,getAuthorities(result.getInteger("access")) );    return userDetails;  }    public Collection<GrantedAuthority> getAuthorities(int access){    List<GrantedAuthority> authList = new ArrayList<GrantedAuthority>(2);    authList.add(new SimpleGrantedAuthority("ROLE_USER"));    if(access==1){      authList.add(new SimpleGrantedAuthority("ROLE_ADMIN"));    }    return authList;  }}