# Class: `KernelSpecs`

[@jupyterlite/kernel](../modules/jupyterlite_kernel.md).KernelSpecs

A class to handle requests to /api/kernelspecs

## Implements

- [`IKernelSpecs`](../modules/jupyterlite_kernel.md#ikernelspecs)

## Constructors

### `constructor`

> **`new KernelSpecs`**()

## Properties

### `_factories`

> `Private` **`_factories`**: `Map`<`string`,
> [`KernelFactory`](../modules/jupyterlite_kernel.KernelSpecs.md#kernelfactory)\>

#### Defined in

[packages/kernel/src/kernelspecs.ts:59](https://github.com/jupyterlite/jupyterlite/blob/7971e0aa/packages/kernel/src/kernelspecs.ts#L59)

### `_specs`

> `Private` **`_specs`**: `Map`<`string`, `ISpecModel`\>

#### Defined in

[packages/kernel/src/kernelspecs.ts:58](https://github.com/jupyterlite/jupyterlite/blob/7971e0aa/packages/kernel/src/kernelspecs.ts#L58)

## Accessors

### `defaultKernelName`

> `get` **`defaultKernelName`**(): `string`

Get the default kernel name.

#### Returns

`string`

#### Implementation of

IKernelSpecs.defaultKernelName

#### Defined in

[packages/kernel/src/kernelspecs.ts:28](https://github.com/jupyterlite/jupyterlite/blob/7971e0aa/packages/kernel/src/kernelspecs.ts#L28)

### `factories`

> `get` **`factories`**():
> [`KernelFactories`](../modules/jupyterlite_kernel.KernelSpecs.md#kernelfactories)

Get the kernel factories for the current kernels.

#### Returns

[`KernelFactories`](../modules/jupyterlite_kernel.KernelSpecs.md#kernelfactories)

#### Implementation of

IKernelSpecs.factories

#### Defined in

[packages/kernel/src/kernelspecs.ts:43](https://github.com/jupyterlite/jupyterlite/blob/7971e0aa/packages/kernel/src/kernelspecs.ts#L43)

### `specs`

> `get` **`specs`**(): `null` \| `ISpecModels`

Get the kernel specs.

#### Returns

`null` \| `ISpecModels`

#### Implementation of

IKernelSpecs.specs

#### Defined in

[packages/kernel/src/kernelspecs.ts:14](https://github.com/jupyterlite/jupyterlite/blob/7971e0aa/packages/kernel/src/kernelspecs.ts#L14)

## Methods

### `register`

> **`register`**(`options`): `void`

Register a new kernel.

#### Parameters

| Name      | Type                                                                               | Description                           |
| :-------- | :--------------------------------------------------------------------------------- | :------------------------------------ |
| `options` | [`IKernelOptions`](../interfaces/jupyterlite_kernel.KernelSpecs.IKernelOptions.md) | The options to register a new kernel. |

#### Returns

`void`

#### Implementation of

IKernelSpecs.register

#### Defined in

[packages/kernel/src/kernelspecs.ts:52](https://github.com/jupyterlite/jupyterlite/blob/7971e0aa/packages/kernel/src/kernelspecs.ts#L52)