How to use the vscode-languageclient.NotificationType function in vscode-languageclient

// Push the disposable to the context's subscriptions so that the
  // client can be deactivated on extension deactivation
  context.subscriptions.push(
    client.start(),
    commands.registerCommand('graphqlForVSCode.showOutputChannel', () => {
      client.outputChannel.show(true);
    }),
    statusBarItem,
  );

  client.onReady().then(() => {
    initializeStatusBar(context, client);
  });
}

const serverInitialized = new NotificationType(
  commonNotifications.serverInitialized,
);
const serverExited = new NotificationType(commonNotifications.serverExited);

function initializeStatusBar(context, client) {
  extensionStatus = Status.init;
  client.onNotification(serverInitialized, params => {
    extensionStatus = Status.ok;
    serverRunning = true;
    updateStatusBar(window.activeTextEditor);
  });
  client.onNotification(serverExited, params => {
    extensionStatus = Status.error;
    serverRunning = false;
    updateStatusBar(window.activeTextEditor);
  });

ownerUri: string;
}

// ------------------------------- < Query Batch Start  Notification > ------------------------------------
export namespace QueryExecuteBatchStartNotification {
    export const type = new NotificationType('query/batchStart');
}

// ------------------------------- < Query Batch Complete Notification > ------------------------------------
export namespace QueryExecuteBatchCompleteNotification {
    export const type = new NotificationType('query/batchComplete');
}

// Query ResultSet Complete Notification -----------------------------------------------------------
export namespace QueryExecuteResultSetCompleteNotification {
    export const type = new NotificationType('query/resultSetComplete');
}

export class QueryExecuteResultSetCompleteNotificationParams {
    resultSetSummary: ResultSetSummary;
    ownerUri: string;
}

// ------------------------------- < Query Message Notification > ------------------------------------
export namespace QueryExecuteMessageNotification {
    export const type = new NotificationType('query/message');
}

export class QueryExecuteMessageParams {
    message: IResultMessage;
    ownerUri: string;
}

export const type = new NotificationType('query/batchComplete');
}

// Query ResultSet Complete Notification -----------------------------------------------------------
export namespace QueryExecuteResultSetCompleteNotification {
    export const type = new NotificationType('query/resultSetComplete');
}

export class QueryExecuteResultSetCompleteNotificationParams {
    resultSetSummary: ResultSetSummary;
    ownerUri: string;
}

// ------------------------------- < Query Message Notification > ------------------------------------
export namespace QueryExecuteMessageNotification {
    export const type = new NotificationType('query/message');
}

export class QueryExecuteMessageParams {
    message: IResultMessage;
    ownerUri: string;
}

// ------------------------------- < Query Execution Request > ------------------------------------
export namespace QueryExecuteRequest {
    export const type = new RequestType('query/executeDocumentSelection');
}

export namespace QueryExecuteStatementRequest {
    export const type = new RequestType('query/executedocumentstatement');
}

uri: string;
    state: CheckStatus;
}

export namespace CheckStatusNotification {
    export const notificationType: NotificationType = new NotificationType('checkstyle/status');
}

export enum ServerStatus {
    downloading,
    running,
    stopped
}

export namespace ServerStatusNotification {
    export const notificationType: NotificationType = new NotificationType('checkstyle/serverstatus');
}

export interface IServerStatusParams {
    readonly status: ServerStatus;
}

export interface IVersionCheckParams {
    readonly uri: string;
    readonly result: VersionCheckResult;
}

export enum VersionCheckResult {
    found,
    invalid,
    exception
}

readonly status: ServerStatus;
}

export interface IVersionCheckParams {
    readonly uri: string;
    readonly result: VersionCheckResult;
}

export enum VersionCheckResult {
    found,
    invalid,
    exception
}

export namespace VersionCheckNotification {
    export const notificationType: NotificationType = new NotificationType('checkstyle/versioncheck');
}

export namespace DownloadStartNotification {
    export const notificationType: NotificationType = new NotificationType('checkstyle/downloadstart');
}

export enum DownloadStatus {
    downloading,
    finished,
    error
}

export namespace DownloadStatusNotification {
    export const notificationType: NotificationType = new NotificationType('checkstyle/downloadstatus');
}

client.onReady().then(() => {
        client.onNotification(new NotificationType('java/colors'), cacheSemanticColors);
        context.subscriptions.push(window.onDidChangeVisibleTextEditors(applySemanticColors));
        workspace.onDidCloseTextDocument(forgetSemanticColors);
    });

complete: boolean;
}

export interface ActionableMessage {
	severity: MessageType;
	message: string;
	data?: any;
	commands?: Command[];
}

export namespace StatusNotification {
	export const type = new NotificationType('language/status');
}

export namespace ProgressReportNotification {
	export const type = new NotificationType('language/progressReport');
}

export namespace ClassFileContentsRequest {
    export const type = new RequestType ('java/classFileContents');
}

export namespace ProjectConfigurationUpdateRequest {
    export const type = new NotificationType ('java/projectConfigurationUpdate');
}

export namespace ActionableNotification {
    export const type = new NotificationType('language/actionableNotification');
}

export namespace CompileWorkspaceRequest {
    export const type = new RequestType('java/buildWorkspace');

import { ExtensionContext, window, commands, workspace, Disposable, languages, IndentAction, env, Uri, ConfigurationTarget, InputBoxOptions } from 'vscode';
import {
	LanguageClient, LanguageClientOptions, ServerOptions,
	TransportKind,
	NotificationType,
    RequestType,
    RevealOutputChannelOn
} from 'vscode-languageclient';
import { createMiddleware, IntelephenseMiddleware } from './middleware';
import * as fs from 'fs-extra';

const PHP_LANGUAGE_ID = 'php';
const VERSION = '1.3.6';
const INDEXING_STARTED_NOTIFICATION = new NotificationType('indexingStarted');
const INDEXING_ENDED_NOTIFICATION = new NotificationType('indexingEnded');
const CANCEL_INDEXING_REQUEST = new RequestType('cancelIndexing');
const INDEX_WORKSPACE_CMD_NAME = 'intelephense.index.workspace';
const CANCEL_INDEXING_CMD_NAME = 'intelephense.cancel.indexing';
const ENTER_KEY_CMD_NAME = 'intelephense.enter.key';
const LICENCE_MEMENTO_KEY = 'intelephense.licence.key';

let languageClient: LanguageClient;
let extensionContext: ExtensionContext;
let middleware:IntelephenseMiddleware;
let clientDisposable:Disposable;

export async function activate(context: ExtensionContext) {

    await moveKeyToGlobalMemento(context);

	languages.setLanguageConfiguration('php', {

import * as semver from 'semver';

import { ExtensionContext, window, commands, workspace, Disposable, languages, IndentAction, env, Uri, ConfigurationTarget, InputBoxOptions } from 'vscode';
import {
	LanguageClient, LanguageClientOptions, ServerOptions,
	TransportKind,
	NotificationType,
    RequestType,
    RevealOutputChannelOn
} from 'vscode-languageclient';
import { createMiddleware, IntelephenseMiddleware } from './middleware';
import * as fs from 'fs-extra';

const PHP_LANGUAGE_ID = 'php';
const VERSION = '1.3.6';
const INDEXING_STARTED_NOTIFICATION = new NotificationType('indexingStarted');
const INDEXING_ENDED_NOTIFICATION = new NotificationType('indexingEnded');
const CANCEL_INDEXING_REQUEST = new RequestType('cancelIndexing');
const INDEX_WORKSPACE_CMD_NAME = 'intelephense.index.workspace';
const CANCEL_INDEXING_CMD_NAME = 'intelephense.cancel.indexing';
const ENTER_KEY_CMD_NAME = 'intelephense.enter.key';
const LICENCE_MEMENTO_KEY = 'intelephense.licence.key';

let languageClient: LanguageClient;
let extensionContext: ExtensionContext;
let middleware:IntelephenseMiddleware;
let clientDisposable:Disposable;

export async function activate(context: ExtensionContext) {

    await moveKeyToGlobalMemento(context);

startChar: number,
    endLine: number,
    endChar: number,
    message: string,
    severity: number
}

export interface StatusParams {
    state: Status,
    message: string,
    uri: string,
    suggestions: Suggestion[]
}

export namespace StatusNotification {
    export const type = new NotificationType('deepscan/status');
}