void populateDisplayData(DisplayData.Builder builder) {
    builder
        .addIfNotNull(
            DisplayData.item("projectId", getProjectId()).withLabel("Bigtable Project Id"))
        .addIfNotNull(
            DisplayData.item("instanceId", getInstanceId()).withLabel("Bigtable Instance Id"))
        .addIfNotNull(
            DisplayData.item("appProfileId", getAppProfileId())
                .withLabel("Bigtable App Profile Id"));

    if (getBigtableOptions() != null) {
      builder.add(
          DisplayData.item("bigtableOptions", getBigtableOptions().toString())
              .withLabel("Bigtable Options"));
    }
  }
@Test
  public void testPopulateDisplayData() {
    DisplayData displayData =
        DisplayData.from(
            config.withProjectId(PROJECT_ID).withInstanceId(INSTANCE_ID)::populateDisplayData);

    assertThat(
        displayData,
        hasDisplayItem(
            allOf(
                hasKey("projectId"), hasLabel("Bigtable Project Id"), hasValue(PROJECT_ID.get()))));

    assertThat(
        displayData,
        hasDisplayItem(
            allOf(
                hasKey("instanceId"),
                hasLabel("Bigtable Instance Id"),
                hasValue(INSTANCE_ID.get()))));
  }