Field Detail

• private final java.util.List<SelectableChannel<? extends T>> channels

• private final boolean[] disabledDFVs

  Since DataflowVariables should be only read once, they need to be disabled after selecting their value The array stores a boolean flag for each index, indicating, whether the channel/variable has been disabled

• private final int numberOfChannels

• private final java.util.Collection<SelectRequest<T>> pendingRequests

  Unsatisfied requests for value, each holding a list of guards and a routine to invoke once a value is available

• @java.lang.SuppressWarnings({"UnsecureRandomNumberGeneration"}) private final java.util.Random position

Constructor Detail

• public SelectBase(PGroup pGroup, java.util.List<SelectableChannel<? extends T>> channels)

  Stores the input channel and registers for the wheneverBound() event on each

  Parameters:

  pGroup - The group, the thread pool of which should be used for notification message handlers

  channels - All the input channels to select on

Method Detail

• @java.lang.SuppressWarnings({"MethodOnlyUsedFromInnerClass"}) void boundNotification(int index, SelectableChannel<? extends T> channel)

  Invoked by the SelectCallback instances, potentially concurrently to inform about new values being available for read from channels.

  throws:

  InterruptedException If the thread is interrupted during value retrieval from the channel

  Parameters:

  index - The index of the ready channel

  channel - The channel itself

• private void disableDFV(int currentPosition, SelectableChannel<? extends T> channel)

  Sets the flag in the disabledDFVs array, if the channel is a DFV

  Parameters:

  currentPosition - The position to mark

  channel - The channel being considered

• public void doSelect(int startIndex, SelectRequest<T> selectRequest)

  Invoked whenever the Select is asked for the next value. Depending on the supplied startIndex value it scans all input channels and reads the first one found, which currently has a value available for read. If no input channel is ready, the supplied SelectRequest instance is registered to be notified by the wheneverBound() channel listeners.

  throws:

  InterruptedException If the thread gets interrupted while reading messages from the channels

  Parameters:

  startIndex - The index of the channel to check first for available messages, -1 if start at a random position. Continue scanning by increasing the index, once the size is reached start from 0.

  selectRequest - The request that holds the guards and expects a notification once a value is selected