Class Context

The execution context of a handler execution.

When Vert.x provides an event to a handler or calls the start or stop methods of a io.vertx.core.Verticle, the execution is associated with a Context.

Usually a context is an event-loop context and is tied to a specific event loop thread. So executions for that context always occur on that exact same event loop thread.

In the case of worker verticles and running inline blocking code a worker context will be associated with the execution which will use a thread from the worker thread pool.

When a handler is set by a thread associated with a specific context, the Vert.x will guarantee that when that handler is executed, that execution will be associated with the same context.

If a handler is set by a thread not associated with a context (i.e. a non Vert.x thread). Then a new context will be created for that handler.

In other words, a context is propagated.

This means that when a verticle is deployed, any handlers it sets will be associated with the same context - the context of the verticle.

This means (in the case of a standard verticle) that the verticle code will always be executed with the exact same thread, so you don't have to worry about multi-threaded acccess to the verticle state and you can code your application as single threaded.

This class also allows arbitrary data to be put and get on the context so it can be shared easily amongst different handlers of, for example, a verticle instance.

This class also provides runOnContext which allows an action to be executed asynchronously using the same context.

Anything
- Object
  - Basic ...and other supertypes
    Context

Context
- Basic
  - Identifiable
  - Object
    Anything

no subtypes hierarchy

Initializer
`Context(Context unknown)`

Inherited Attributes
Attributes inherited from: `Object` `hash`, `string`

Methods
`config`	`shared default Object? config()` If the context is associated with a Verticle deployment, this returns the configuration that was specified when the verticle was deployed.
`deploymentID`	`shared default String deploymentID()` If the context is associated with a Verticle deployment, this returns the deployment ID of that deployment.
`exceptionHandler`	`shared default Context exceptionHandler(Anything(Throwable)? handler)` Set an exception handler called when the context runs an action throwing an uncaught throwable. When this handler is called, currentContext will return this context. Parameters: `handler` the exception handler
`executeBlocking`	`shared default void executeBlocking<T>(Anything(Future<T?>) blockingCodeHandler, Anything(Throwable\|T?) resultHandler)` Invoke executeBlocking with order = true. Parameters: `blockingCodeHandler` handler representing the blocking code to run `resultHandler` handler that will be called when the blocking code is complete
`executeBlocking`	`shared default void executeBlocking<T>(Anything(Future<T?>) blockingCodeHandler, Boolean ordered, Anything(Throwable\|T?) 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 complete or complete method, or the fail method if it failed. Parameters: `blockingCodeHandler` handler representing the blocking code to run `ordered` 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` handler that will be called when the blocking code is complete
`get`	`shared default T? get<T>(String key)` Get some data from the context. Parameters: `key` the key of the data
`getInstanceCount`	`shared default Integer getInstanceCount()`
`isEventLoopContext`	`shared default Boolean isEventLoopContext()` Is the current context an event loop context? NOTE! when running blocking code using executeBlocking from a standard (not worker) verticle, the context will still an event loop context and this will return true.
`isMultiThreadedWorkerContext`	`shared default Boolean isMultiThreadedWorkerContext()` Is the current context a multi-threaded worker context?
`isWorkerContext`	`shared default Boolean isWorkerContext()` Is the current context a worker context? NOTE! when running blocking code using executeBlocking from a standard (not worker) verticle, the context will still an event loop context and this will return false.
`owner`	`shared default Vertx owner()`
`processArgs`	`shared default List<String> processArgs()` The process args
`put`	`shared default void put(String key, Object? value)` Put some data in the context. This can be used to share data between different handlers that share a context Parameters: `key` the key of the data `value` the data
`remove`	`shared default Boolean remove(String key)` Remove some data from the context. Parameters: `key` the key to remove
`runOnContext`	`shared default void runOnContext(Anything() action)` Run the specified action asynchronously on the same context, some time after the current execution has completed. Parameters: `action` the action to run

Inherited Methods
Methods inherited from: `Object` `equals`

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