public boolean hasUpdateMask() {
      return ((bitField0_ & 0x00000001) != 0);
    }
<pre>
Required. Field mask is used to specify the fields to be overwritten in the
`ManagementDnsZoneBinding` resource by the update.
The fields specified in the `update_mask` are relative to the resource, not
the full request. A field will be overwritten if it is in the mask. If the
user does not provide a mask then all fields will be overwritten.
</pre>

<code>.google.protobuf.FieldMask update_mask = 1 [(.google.api.field_behavior) = REQUIRED];
</code>

@return Whether the updateMask field is set.
java-vmwareengine/proto-google-cloud-vmwareengine-v1/src/main/java/com/google/cloud/vmwareengine/v1/UpdateManagementDnsZoneBindingRequest.java