/** * * * <pre> * Optional. Field mask that specifies the fields in `sink` that need * an update. A sink field will be overwritten if, and only if, it is * in the update mask. `name` and output only fields cannot be updated. * An empty updateMask is temporarily treated as using the following mask * for backwards compatibility purposes: * destination,filter,includeChildren * At some point in the future, behavior will be removed and specifying an * empty updateMask will be an error. * For a detailed `FieldMask` definition, see * https://developers.google.com/protocol-buffers/docs/reference/google.protobuf#google.protobuf.FieldMask * Example: `updateMask=filter`. * </pre> * * <code>.google.protobuf.FieldMask update_mask = 4;</code> */ public com.google.protobuf.FieldMask.Builder getUpdateMaskBuilder() { onChanged(); return getUpdateMaskFieldBuilder().getBuilder(); } /**