# Class: Vertx

## vertx-js/vertx~ Vertx

#### new Vertx()

The entry point into the Vert.x Core API.

You use an instance of this class for functionality including:

- Creating TCP clients and servers
- Creating HTTP clients and servers
- Creating DNS clients
- Creating Datagram sockets
- Setting and cancelling periodic and one-shot timers
- Getting a reference to the event bus API
- Getting a reference to the file system API
- Getting a reference to the shared data API
- Deploying and undeploying verticles

Most functionality in Vert.x core is fairly low level.

Source:
  - vertx-js/vertx.js, line 65

### Methods

#### cancelTimer(id) → {boolean}

Cancels the timer with the specified `id`.

##### Parameters:

Name | Type | Description
--- | --- | ---
`id` | number | The id of the timer to cancel

Source:
  - vertx-js/vertx.js, line 318

##### Returns:

true if the timer was successfully cancelled, or false if the timer does not exist.

Type
  boolean

#### close(completionHandler)

Like Vertx#close but the completionHandler will be called when the close is complete

##### Parameters:

Name | Type | Description
--- | --- | ---
`completionHandler` | function | The handler will be notified when the close is complete.

Source:
  - vertx-js/vertx.js, line 345

#### createDatagramSocket(options) → {DatagramSocket}

Create a datagram socket using the specified options

##### Parameters:

Name | Type | Description
--- | --- | ---
`options` | Object | the options to use

Source:
  - vertx-js/vertx.js, line 170

##### Returns:

the socket

Type
  DatagramSocket

#### createDnsClient(port, host) → {DnsClient}

Create a DNS client to connect to a DNS server at the specified host and port

##### Parameters:

Name | Type | Description
--- | --- | ---
`port` | number | the port
`host` | string | the host

Source:
  - vertx-js/vertx.js, line 221

##### Returns:

the DNS client

Type
  DnsClient

#### createHttpClient(options) → {HttpClient}

Create a HTTP/HTTPS client using the specified options

##### Parameters:

Name | Type | Description
--- | --- | ---
`options` | Object | the options to use

Source:
  - vertx-js/vertx.js, line 154

##### Returns:

the client

Type
  HttpClient

#### createHttpServer(options) → {HttpServer}

Create an HTTP/HTTPS server using the specified options

##### Parameters:

Name | Type | Description
--- | --- | ---
`options` | Object | the options to use

Source:
  - vertx-js/vertx.js, line 138

##### Returns:

the server

Type
  HttpServer

#### createNetClient(options) → {NetClient}

Create a TCP/SSL client using the specified options

##### Parameters:

Name | Type | Description
--- | --- | ---
`options` | Object | the options to use

Source:
  - vertx-js/vertx.js, line 122

##### Returns:

the client

Type
  NetClient

#### createNetServer(options) → {NetServer}

Create a TCP/SSL server using the specified options

##### Parameters:

Name | Type | Description
--- | --- | ---
`options` | Object | the options to use

Source:
  - vertx-js/vertx.js, line 106

##### Returns:

the server

Type
  NetServer

#### createSharedWorkerExecutor(name, poolSize, maxExecuteTime) → {WorkerExecutor}

Create a named worker executor, the executor should be closed when it's not needed anymore to release resources.

This method can be called mutiple times with the same `name`. Executors with the same name will share the same worker pool. The worker pool size and max execute time are set when the worker pool is created and won't change after.

The worker pool is released when all the WorkerExecutor sharing the same name are closed.

##### Parameters:

Name | Type | Description
--- | --- | ---
`name` | string | the name of the worker executor
`poolSize` | number | the size of the pool
`maxExecuteTime` | number | the value of max worker execute time, in ns

Source:
  - vertx-js/vertx.js, line 505

##### Returns:

the named worker executor

Type
  WorkerExecutor

#### deploymentIDs() → {Array.<string>}

Return a Set of deployment IDs for the currently deployed deploymentIDs.

Source:
  - vertx-js/vertx.js, line 423

##### Returns:

Set of deployment IDs

Type
  Array.<string>

#### deployVerticle(name, options, completionHandler)

Like Vertx#deployVerticle but DeploymentOptions are provided to configure the deployment.

##### Parameters:

Name | Type | Description
--- | --- | ---
`name` | string | the name
`options` | Object | the deployment options.
`completionHandler` | function | a handler which will be notified when the deployment is complete

Source:
  - vertx-js/vertx.js, line 369

#### eventBus() → {EventBus}

Get the event bus object. There is a single instance of EventBus per Vertx instance.

Source:
  - vertx-js/vertx.js, line 203

##### Returns:

the event bus object

Type
  EventBus

#### exceptionHandler(handler) → {Vertx}

Set a default exception handler for Context, set on at creation.

##### Parameters:

Name | Type | Description
--- | --- | ---
`handler` | function | the exception handler

Source:
  - vertx-js/vertx.js, line 523

##### Returns:

a reference to this, so the API can be used fluently

Type
  Vertx

#### executeBlocking(blockingCodeHandler, ordered, resultHandler)

Safely execute some blocking code.

Executes the blocking code in the handler `blockingCodeHandler` using a thread from the worker pool.

When the code is complete the handler `resultHandler` will be called with the result on the original context (e.g. on the original event loop of the caller).

A `Future` instance is passed into `blockingCodeHandler`. When the blocking code successfully completes, the handler should call the Future#complete or Future#complete method, or the Future#fail method if it failed.

In the `blockingCodeHandler` the current context remains the original context and therefore any task scheduled in the `blockingCodeHandler` will be executed on the this context and not on the worker thread.

##### Parameters:

Name | Type | Description
--- | --- | ---
`blockingCodeHandler` | function | handler representing the blocking code to run
`ordered` | boolean | if true then if executeBlocking is called several times on the same context, the executions for that context will be executed serially, not in parallel. if false then they will be no ordering guarantees
`resultHandler` | function | handler that will be called when the blocking code is complete

Source:
  - vertx-js/vertx.js, line 464

#### fileSystem() → {FileSystem}

Get the filesystem object. There is a single instance of FileSystem per Vertx instance.

Source:
  - vertx-js/vertx.js, line 186

##### Returns:

the filesystem object

Type
  FileSystem

#### getOrCreateContext() → {Context}

Gets the current context, or creates one if there isn't one

Source:
  - vertx-js/vertx.js, line 92

##### Returns:

The current context (created if didn't exist)

Type
  Context

#### isClustered() → {boolean}

Is this Vert.x instance clustered?

Source:
  - vertx-js/vertx.js, line 437

##### Returns:

true if clustered

Type
  boolean

#### isMetricsEnabled() → {boolean}

Whether the metrics are enabled for this measured object

Source:
  - vertx-js/vertx.js, line 78

##### Returns:

true if the metrics are enabled

Type
  boolean

#### periodicStream(delay) → {TimeoutStream}

Returns a periodic timer as a read stream. The timer will be fired every `delay` milliseconds after the has been called.

##### Parameters:

Name | Type | Description
--- | --- | ---
`delay` | number | the delay in milliseconds, after which the timer will fire

Source:
  - vertx-js/vertx.js, line 304

##### Returns:

the periodic stream

Type
  TimeoutStream

#### runOnContext(action)

Puts the handler on the event queue for the current context so it will be run asynchronously ASAP after all preceeding events have been handled.

##### Parameters:

Name | Type | Description
--- | --- | ---
`action` | function | a handler representing the action to execute

Source:
  - vertx-js/vertx.js, line 332

#### setPeriodic(delay, handler) → {number}

Set a periodic timer to fire every `delay` milliseconds, at which point `handler` will be called with the id of the timer.

##### Parameters:

Name | Type | Description
--- | --- | ---
`delay` | number | the delay in milliseconds, after which the timer will fire
`handler` | function | the handler that will be called with the timer ID when the timer fires

Source:
  - vertx-js/vertx.js, line 287

##### Returns:

the unique ID of the timer

Type
  number

#### setTimer(delay, handler) → {number}

Set a one-shot timer to fire after `delay` milliseconds, at which point `handler` will be called with the id of the timer.

##### Parameters:

Name | Type | Description
--- | --- | ---
`delay` | number | the delay in milliseconds, after which the timer will fire
`handler` | function | the handler that will be called with the timer ID when the timer fires

Source:
  - vertx-js/vertx.js, line 254

##### Returns:

the unique ID of the timer

Type
  number

#### sharedData() → {SharedData}

Get the shared data object. There is a single instance of SharedData per Vertx instance.

Source:
  - vertx-js/vertx.js, line 235

##### Returns:

the shared data object

Type
  SharedData

#### timerStream(delay) → {TimeoutStream}

Returns a one-shot timer as a read stream. The timer will be fired after `delay` milliseconds after the has been called.

##### Parameters:

Name | Type | Description
--- | --- | ---
`delay` | number | the delay in milliseconds, after which the timer will fire

Source:
  - vertx-js/vertx.js, line 271

##### Returns:

the timer stream

Type
  TimeoutStream

#### undeploy(deploymentID, completionHandler)

Like [#undeploy(String)] Vertx but the completionHandler will be notified when the undeployment is complete.

##### Parameters:

Name | Type | Description
--- | --- | ---
`deploymentID` | string | the deployment ID
`completionHandler` | function | a handler which will be notified when the undeployment is complete

Source:
  - vertx-js/vertx.js, line 401