doctrine / orm

                $discriminatorColumn = new Mapping\DiscriminatorColumnMetadata();

                // Evaluate @DiscriminatorColumn annotation

                if (isset($classAnnotations[Annotation\DiscriminatorColumn::class])) {

                    /** @var Annotation\DiscriminatorColumn $discriminatorColumnAnnot */

                    $discriminatorColumnAnnot = $classAnnotations[Annotation\DiscriminatorColumn::class];

                    $discriminatorColumn->setColumnName($discriminatorColumnAnnot->name);

                    if (! empty($discriminatorColumnAnnot->columnDefinition)) {

                        $discriminatorColumn->setColumnDefinition($discriminatorColumnAnnot->columnDefinition);

                    }

                    if (! empty($discriminatorColumnAnnot->type)) {

                        $discriminatorColumn->setType(Type::getType($discriminatorColumnAnnot->type));

                    }

                    if (! empty($discriminatorColumnAnnot->length)) {

                        $discriminatorColumn->setLength($discriminatorColumnAnnot->length);

                    }

                }

                if (empty($discriminatorColumn->getColumnName())) {

                    throw Mapping\MappingException::nameIsMandatoryForDiscriminatorColumns($reflectionClass->getName());

                $discriminatorColumn->setLength(255);

                // Evaluate DiscriminatorColumn annotation

                if (isset($classAnnotations[Annotation\DiscriminatorColumn::class])) {

                    /** @var Annotation\DiscriminatorColumn $discriminatorColumnAnnotation */

                    $discriminatorColumnAnnotation = $classAnnotations[Annotation\DiscriminatorColumn::class];

                    $typeName                      = ! empty($discriminatorColumnAnnotation->type)

                        ? $discriminatorColumnAnnotation->type

                        : 'string';

                    $discriminatorColumn->setType(Type::getType($typeName));

                    $discriminatorColumn->setColumnName($discriminatorColumnAnnotation->name);

                    if (! empty($discriminatorColumnAnnotation->columnDefinition)) {

                        $discriminatorColumn->setColumnDefinition($discriminatorColumnAnnotation->columnDefinition);

                    }

                    if (! empty($discriminatorColumnAnnotation->length)) {

                        $discriminatorColumn->setLength($discriminatorColumnAnnotation->length);

                    }

                }

                $classMetadata->setDiscriminatorColumn($discriminatorColumn);