@java.lang.Override
  public boolean equals(final java.lang.Object obj) {
    if (obj == this) {
      return true;
    }
    if (!(obj instanceof com.google.cloud.visionai.v1.UpdateIndexRequest)) {
      return super.equals(obj);
    }
    com.google.cloud.visionai.v1.UpdateIndexRequest other =
        (com.google.cloud.visionai.v1.UpdateIndexRequest) obj;

    if (hasIndex() != other.hasIndex()) return false;
    if (hasIndex()) {
      if (!getIndex().equals(other.getIndex())) return false;
    }
    if (hasUpdateMask() != other.hasUpdateMask()) return false;
    if (hasUpdateMask()) {
      if (!getUpdateMask().equals(other.getUpdateMask())) return false;
    }
    if (!getUnknownFields().equals(other.getUnknownFields())) return false;
    return true;
  }
<pre>
Required. Field mask is used to specify the fields to be overwritten in the
Index resource by the update. The fields specified in the update_mask are
relative to the resource, not the full request. A field of the resource
will be overwritten if it is in the mask. Empty field mask is not allowed.
If the mask is "*", it triggers a full update of the index, and also a
whole rebuild of index data.
</pre>

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