com.r3corda.node.services.api / MessagingServiceInternal

# MessagingServiceInternal

`interface MessagingServiceInternal : MessagingService`

### Inherited Properties

myAddress | `abstract val myAddress: SingleMessageRecipient` Returns an address that refers to this node.

### Functions

stop | `abstract fun stop(): Unit` Initiates shutdown: if called from a thread that isnt controlled by the executor passed to the constructor then this will block until all in-flight messages have finished being handled and acknowledged. If called from a thread thats a part of the AffinityExecutor given to the constructor, it returns immediately and shutdown is asynchronous.

### Inherited Functions

addMessageHandler | `abstract fun addMessageHandler(topic: String = "", sessionID: Long = DEFAULT_SESSION_ID, executor: Executor? = null, callback: (Message, MessageHandlerRegistration) -> Unit): MessageHandlerRegistration` The provided function will be invoked for each received message whose topic matches the given string, on the given executor. `abstract fun addMessageHandler(topicSession: TopicSession, executor: Executor? = null, callback: (Message, MessageHandlerRegistration) -> Unit): MessageHandlerRegistration` The provided function will be invoked for each received message whose topic and session matches, on the given executor.
createMessage | `abstract fun createMessage(topic: String, sessionID: Long = DEFAULT_SESSION_ID, data: ByteArray): Message` `abstract fun createMessage(topicSession: TopicSession, data: ByteArray): Message` Returns an initialised Message with the current time, etc, already filled in.
removeMessageHandler | `abstract fun removeMessageHandler(registration: MessageHandlerRegistration): Unit` Removes a handler given the object returned from addMessageHandler. The callback will no longer be invoked once this method has returned, although executions that are currently in flight will not be interrupted.
send | `abstract fun send(message: Message, target: MessageRecipients): Unit` Sends a message to the given receiver. The details of how receivers are identified is up to the messaging implementation: the type system provides an opaque high level view, with more fine grained control being available via type casting. Once this function returns the message is queued for delivery but not necessarily delivered: if the recipients are offline then the message could be queued hours or days later.

### Extension Functions

runOnNextMessage | `fun MessagingService.runOnNextMessage(topic: String, sessionID: Long, executor: Executor? = null, callback: (Message) -> Unit): Unit` Registers a handler for the given topic and session ID that runs the given callback with the message and then removes itself. This is useful for one-shot handlers that arent supposed to stick around permanently. Note that this callback doesnt take the registration object, unlike the callback to MessagingService.addMessageHandler, as the handler is automatically deregistered before the callback runs. `fun MessagingService.runOnNextMessage(topicSession: TopicSession, executor: Executor? = null, callback: (Message) -> Unit): Unit` Registers a handler for the given topic and session that runs the given callback with the message and then removes itself. This is useful for one-shot handlers that arent supposed to stick around permanently. Note that this callback doesnt take the registration object, unlike the callback to MessagingService.addMessageHandler.
send | `fun MessagingService.send(topic: String, sessionID: Long, payload: Any, to: MessageRecipients): Unit` `fun MessagingService.send(topicSession: TopicSession, payload: Any, to: MessageRecipients): Unit`

### Inheritors

ArtemisMessagingClient | `class ArtemisMessagingClient : ArtemisMessagingComponent, MessagingServiceInternal` This class implements the MessagingService API using Apache Artemis, the successor to their ActiveMQ product. Artemis is a message queue broker and here we run a client connecting to the specified broker instance ArtemisMessagingServer.
InMemoryMessaging | `inner class InMemoryMessaging : SingletonSerializeAsToken, MessagingServiceInternal` An InMemoryMessaging provides a MessagingService that isnt backed by any kind of network or disk storage system, but just uses regular queues on the heap instead. It is intended for unit testing and developer convenience when all entities on the network are being simulated in-process.