@java.lang.Override
  public final boolean isInitialized() {
    byte isInitialized = memoizedIsInitialized;
    if (isInitialized == 1) return true;
    if (isInitialized == 0) return false;

    memoizedIsInitialized = 1;
    return true;
  }
<pre>
Required. Update mask is used to specify the fields to be overwritten in
the `blueprint` resource by the update.
</pre>

<code>.google.protobuf.FieldMask update_mask = 2 [(.google.api.field_behavior) = REQUIRED];
</code>
java-telcoautomation/proto-google-cloud-telcoautomation-v1/src/main/java/com/google/cloud/telcoautomation/v1/UpdateBlueprintRequest.java