code: public BuildableType.Builder mergeFrom(BuildableType value) {
      BuildableType_Builder defaults = new BuildableType.Builder();
      if (defaults._unsetProperties.contains(Property.TYPE)
          || !Objects.equals(value.type(), defaults.type())) {
        type(value.type());
      }
      if (defaults._unsetProperties.contains(Property.BUILDER_TYPE)
          || !Objects.equals(value.builderType(), defaults.builderType())) {
        builderType(value.builderType());
      }
      if (defaults._unsetProperties.contains(Property.MERGE_BUILDER)
          || !Objects.equals(value.mergeBuilder(), defaults.mergeBuilder())) {
        mergeBuilder(value.mergeBuilder());
      }
      if (defaults._unsetProperties.contains(Property.PARTIAL_TO_BUILDER)
          || !Objects.equals(value.partialToBuilder(), defaults.partialToBuilder())) {
        partialToBuilder(value.partialToBuilder());
      }
      if (defaults._unsetProperties.contains(Property.BUILDER_FACTORY)
          || !Objects.equals(value.builderFactory(), defaults.builderFactory())) {
        builderFactory(value.builderFactory());
      }
      if (defaults._unsetProperties.contains(Property.SUPPRESS_UNCHECKED)
          || !Objects.equals(value.suppressUnchecked(), defaults.suppressUnchecked())) {
        suppressUnchecked(value.suppressUnchecked());
      }
      return (BuildableType.Builder) this;
    }
docs: Copies values from {@code value}.
  
  @return this {@code Builder} object