public static BlockLocation getCached(
      long workerId, String tierAlias, String mediumType) {
    BlockLocation location = BlockLocation
        .newBuilder()
        .setWorkerId(workerId)
        .setTier(tierAlias)
        .setMediumType(mediumType)
        .build();
    return getCached(location);
  }
@Test(expected = IllegalStateException.class)
  public void testInvalidValue() {
    BlockLocationUtils.getCached(1, "INVALID", "SSD");
  }