Components\Model\Model::beforeValidationOnCreate PHP Method

    public function beforeValidationOnCreate()
    {
        $metadata = $this->getModelsMetaData();
        $defaults = $metadata->getDefaultValues($this);
        $attributes = $metadata->getNotNullAttributes($this);
        # set all not null fields to their default value.
        foreach ($attributes as $field) {
            if (!property_exists($this, $field)) {
                continue;
            }
            if (isset($this->{$field}) || !is_null($this->{$field}) || !isset($defaults[$field])) {
                continue;
            }
            $this->{$field} = new RawValue($defaults[$field]);
        }
    }