Package com.qfs.messenger

Interface IDistributedMessenger

All Superinterfaces:
IAgent, IExtendedPluginValue, IMonitoredComponent
All Known Implementing Classes:
ADistributedMessenger, AJGroupsMessenger, LocalMessenger, LogNettyMessenger, NettyMessenger
public interface IDistributedMessenger extends IAgent, IMonitoredComponent
An object used to broadcast messages to other instances and process remote messages.
Author:
ActiveViam

  • Field Details

  • Method Details

    • broadcast

      <AnswerT, OutputT> OutputT broadcast(IBroadcastMessage<AnswerT,OutputT,?> message, long timeout) throws Exception
      Broadcasts the given message to all instances, collects the answers and processes them to produce the global answer.

      The whole process is done synchronously on the current thread.

      Type Parameters:
      AnswerT - the result type of the message execution on a remote instance
      OutputT - the result type of the message after receiving all AnswerType
      Parameters:
      message - The message to broadcast
      timeout - The time (in ms) after which we consider that this broadcast has timed out if we did not get a reply from all the addressees.
      Returns:
      The global answer to this message
      Throws:
      Exception - if a exception is raised when broadcasting the message. answers

    • broadcastAsynchronously

      <AnswerT, OutputT> CompletionStage<OutputT> broadcastAsynchronously(IBroadcastMessage<AnswerT,OutputT,?> message, long timeout) throws Exception
      Broadcasts the given message to all remote instances asynchronously, and executes it locally asynchronously as well.

      The message will then be automatically processed by invoking IBroadcastMessage.processReplies(Collection) asynchronously in another thread when the remote answers have been received.

      There are no strong guarantees that the processing will ever be done, since the message may time out and never come back.

      Type Parameters:
      AnswerT - the result type of the message execution on a remote instance
      OutputT - the result type of the message after receiving all AnswerType
      Parameters:
      message - The message to broadcast
      timeout - The time (in ms) after which we consider that this broadcast has timed out if we did not get a reply from all the addressees.
      Returns:
      A stage of the asynchronous transmission of the message. It could be used to trigger actions when the message has been transmitted either normally or abnormally.
      Throws:
      Exception - if a exception is raised when broadcasting the message.

    • sendMessage

      <AnswerT, OutputT> OutputT sendMessage(IBroadcastMessage<AnswerT,OutputT,?> message, Collection<String> addresses, long timeout) throws Exception
      Sends the given message to some specific instances, collects the answers and process them to produce the global answer.

      The whole process is done synchronously on the current thread.

      Type Parameters:
      AnswerT - the result type of the message execution on a remote instance
      OutputT - the result type of the message after receiving all AnswerType
      Parameters:
      message - The message to broadcast
      addresses - The addresses of the members to send the message to
      timeout - The time (in ms) after which we consider that this broadcast has timed out if we did not get a reply from all the addressees.
      Returns:
      The global answer to this message
      Throws:
      Exception - if a exception is raised when sending the message.

    • sendMessageAsynchronously

      <AnswerT, OutputT> CompletableFuture<OutputT> sendMessageAsynchronously(IBroadcastMessage<AnswerT,OutputT,?> message, Collection<String> addresses, long timeout)
      Sends the given message to some specific remote instances asynchronously.

      The message will then be automatically processed by invoking IBroadcastMessage.processReplies(Collection) asynchronously in another thread when the remote answers have been received.

      There are no strong guarantees that the processing will ever be done, since the message may time out and never come back.

      Type Parameters:
      AnswerT - the result type of the message execution on a remote instance
      OutputT - the result type of the message after receiving all AnswerType
      Parameters:
      message - The message to broadcast
      addresses - The addresses of the members to send the message to
      timeout - The time (in ms) after which we consider that this broadcast has timed out if we did not get a reply from all the addressees.
      Returns:
      A stage of the asynchronous transmission of the message. It could be used to trigger actions when the message has been transmitted either normally or abnormally.

    • getDefaultTimeout

      long getDefaultTimeout()
      Returns the default timeout in milliseconds to use for the messages sent by this messenger.

    • awaitNewView

      long awaitNewView(long viewId, long timeout, TimeUnit unit) throws InterruptedException, TimeoutException
      Waits at most the given time for the view ID to be strictly greater than the given one.
      Parameters:
      viewId - The current view ID
      timeout - A timeout
      unit - The timeout's time unit
      Returns:
      The new view Id
      Throws:
      InterruptedException - if any thread interrupted the current thread before or while the current thread was waiting for a notification. The interrupted status of the current thread is cleared when this exception is thrown.
      TimeoutException - if the wait timed out

    • awaitViewNotification

      long awaitViewNotification(long viewId, long timeout, TimeUnit unit) throws InterruptedException, TimeoutException
      It waits for the given timeout for the viewId to be applied.
      Parameters:
      viewId - The current view ID
      timeout - A timeout
      unit - The timeout's time unit
      Returns:
      The new view Id
      Throws:
      InterruptedException - if any thread interrupted the current thread before or while the current thread was waiting for a notification. The interrupted status of the current thread is cleared when this exception is thrown.
      TimeoutException - if the wait timed out

    • register

      boolean register(IDistributedAgent agent) throws AgentException
      Register the given IDistributedAgent.
      Parameters:
      agent - An IDistributedAgent
      Returns:
      true if this agent is being registered for the first time
      Throws:
      AgentException - if the Agent cannot be registered

    • restart

      void restart()
      Restart the messenger.

    • unregister

      boolean unregister(IDistributedAgent agent) throws AgentException
      Unregister the given IDistributedAgent.
      Parameters:
      agent - An IDistributedAgent
      Returns:
      true if this agent has been successfully unregistered
      Throws:
      AgentException - if the Agent cannot be unregistered.

    • getRegisteredAgents

      Set<IDistributedAgent> getRegisteredAgents()
      Returns all the registered IDistributedAgents. The returned set is a copy of the currently registered IDistributedAgents and is therefore thread-safe.
      Returns:
      All the registered IDistributedAgents

    • getAddressAsString

      String getAddressAsString()
      Returns the address of the current (local) instance.

    • getAddress

      IAddress getAddress()
      Returns the IAddress of the current (local) instance.

    • setMessageContext

      <ContextT> void setMessageContext(Class<ContextT> contextType, ContextT context)
      Sets a local message context for a given type. This should never be called concurrently with another setMessageContext(Class, Object) or a getMessageContext(Class).
      Type Parameters:
      ContextT - the context associated to the message. It is set before the message computation on a remote instance
      Parameters:
      contextType - The context type
      context - The actual context object

    • getMessageContext

      <ContextT> ContextT getMessageContext(Class<ContextT> contextType)
      Returns the local message context of the given kind.
      Type Parameters:
      ContextT - the context associated to the message. It is set before the message computation on a remote instance
      Parameters:
      contextType - The type of context we want
      Returns:
      The local context of the requested type

    • getExecutorService

      IDistributedExecutorService getExecutorService()
      Returns the ExecutorService used by the messenger.

    • getView

      IClusterView getView()
      Returns the IClusterView of the current cluster.

      If the messenger is not started or paused, null is returned. Otherwise, a non-null value is returned.
      Notice it returns the most recent view of the cluster each time this method is called. By consequence, two consecutive calls to this method may return a different result.