我的目标是填补空缺 UserDto pojo使用“usersmapper”mybatisMap器。

public class UserDto {
  private String username;
  private String password;
  private List<String> authorities;

  public String getUsername() {
    return username;
  }

  public String getPassword() {
    return password;
  }

  public Set<SimpleGrantedAuthority> getAuthorities() {
    return authorities.stream()
            .map(SimpleGrantedAuthority::new)
            .collect(Collectors.toSet());
  }
}

@Mapper
public interface UsersMapper {
  @Select("SELECT users.username, users.password, role_authorities.authority " +
          "FROM users " +
          "JOIN role_members ON role_members.username = users.username " +
          "AND users.username=#{username} " +
          "JOIN role_authorities ON role_authorities.role_uuid = role_members.role_uuid")
  Optional<UserDto> getUsers(String username);
}

这就是我直接运行sql语句的样子。

我的预期结果是：mybatis成功地填补了 UserDto 波乔。
我的实际结果是我得到了一个例外

org.springframework.security.authentication.InternalAuthenticationServiceException: nested exception is org.apache.ibatis.exceptions.TooManyResultsException: Expected one result (or null) to be returned by selectOne(), but found: 3