mybatis集合结果集maaping问题。获取空集合结果集

Question

我是mybatis的新手，面临在结果集中获取集合的问题。结果集定义如下：

<resultMap type="User" id="userMap">
        <id column="id" property="id" />
        <result property="userName" column="user_name" />
        <result property="enabled" column="enabled" />
        <result property="firstName" column="first_name" />
        <result property="lastName" column="last_name" />
        <result property="email" column="email" />
        <result property="password" column="user_password" />
        <result property="passwordSalt" column="user_password_salt" />
        <result property="lastLogin" column="last_login_time" />
        <result property="creationTime" column="creation_time" />
        <result property="lastEdit" column="last_edit_time" />
        <result property="validTill" column="valid_till" />

        <collection property="roles" javaType="ArrayList" ofType="Role" column="id">
            <id property="id" column="role_id" />
            <result property="name" column="role_name" />
            <result property="description" column="role_description" />
        </collection>

    </resultMap>

Java代码看起来像这样

protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken token)
    throws AuthenticationException
  {
    UsernamePasswordToken upToken = (UsernamePasswordToken)token;

    User user = null;
    user = new UserService().getWithRole(upToken.getUsername());
    if (user == null) {
      throw new UnknownAccountException("Login name [" + upToken.getUsername() + "] not found!");
    }
    if (!user.getEnabled().booleanValue()) {
      throw new DisabledAccountException("Login name [" + upToken.getUsername() + "] is disabled!");
    }
    if (user.getRoles().size() == 0) {
      throw new AuthenticationException("There is no role assigned for you");
    }
    if ((user.getValidTill() != null) && (user.getValidTill().getTime() < new Date().getTime())) {
      throw new ExpiredCredentialsException("Your account has expired!");
    }
    _logger.debug("Found user with username [" + upToken.getUsername() + "]");
    return new SimpleAuthenticationInfo(user, user.getPassword(), new SimpleByteSource(user.getPasswordSalt()), getName());
  }

在这里，登录时我遇到了异常There is no role assigned to you

关于代码是正确的，它工作得很好但是我不能做任何改变，因为我只使用了我正在使用JD进行反编译的WAR。函数getWithRole()触发以下查询

<select id="getWithRole" resultMap="userMap" parameterType="User">
    SELECT * FROM view_boss_user_role
    <trim prefix="WHERE" prefixOverrides="AND | OR ">
        <if test="id != null">id = #{id}</if>
        <if test="userName != null">AND user_name = #{userName}</if>
        <if test="firstName != null">AND first_name = #{firstName}</if>
        <if test="lastName != null">AND last_name = #{lastName}</if>
        <if test="email != null">AND email = #{email}</if>
    </trim>
</select>

并且视图的结构是这样的

CREATE OR REPLACE VIEW public.view_boss_user_role(
    id,
    user_name,
    enabled,
    first_name,
    last_name,
    email,
    user_password,
    user_password_salt,
    last_login_time,
    creation_time,
    last_edit_time,
    valid_till,
    role_id,
    role_name,
    role_description)
AS
  SELECT boss_user.id,
         boss_user.user_name,
         boss_user.enabled,
         boss_user.first_name,
         boss_user.last_name,
         boss_user.email,
         boss_user.user_password,
         boss_user.user_password_salt,
         boss_user.last_login_time,
         boss_user.creation_time,
         boss_user.last_edit_time,
         boss_user.valid_till,
         boss_role.id AS role_id,
         boss_role.name AS role_name,
         boss_role.description AS role_description
  FROM boss_user,
       boss_role,
       boss_role_user_map
  WHERE boss_role_user_map.user_id = boss_user.id AND
        boss_role.id = boss_role_user_map.role_id;

示例输出如下所示

"id"    "user_name" "enabled"   "first_name"    "last_name" "email" "user_password" "user_password_salt"    "last_login_time"   "creation_time" "last_edit_time"    "valid_till"    "role_id"   "role_name" "role_description"
"1" "adminuser" "True"  "Admin" "User"  "adminuser@domain.com"  "SEli9hsMTTxGgjrlCz48+5w1CaMnUe/8xJJ0enOZ2ag="  "mBPa0wNPjvnGK3gzDMOHOg=="  "28-05-2017"    "28-05-2017"    "28-05-2017"    "31-05-2018"    "1" "ADMIN" "Administrator user"

我坚持这个错误，我很确定这是对mybatis的理解限制了我。请赐教我