Represents a synchronous deterministic dataflow channel. Unlike a SyncDataflowQueue, syncDataflowStream allows multiple readers each to read all the messages. Essentially, you may think of SyncDataflowStream as a 1 to many communication channel, since when a reader consumes a messages, other readers will still be able to read the message. Also, all messages arrive to all readers in the same order. SyncDataflowStream is implemented as a functional queue, which impacts the API in that users have to traverse the values in the stream themselves. On the other hand in offers handy methods for value filtering or transformation together with interesting performance characteristics. For convenience and for the ability to use SyncDataflowStream with other dataflow constructs, like e.g. operators, you can wrap SyncDataflowStreams with DataflowReadAdapter for read access or DataflowWriteAdapter for write access.
The SyncDataflowStream class is designed for single-threaded producers and consumers. If multiple threads are supposed to read or write values to the stream, their access to the stream must be serialized externally or the adapters should be used.
SyncDataflowStream uses SyncDataflowVariables to preform the actual data exchange. Unlike DataflowStream, which exchanges data in asynchronous manner, SyncDataflowStream is synchronous. The writer as well as the readers are blocked until all the required parties become ready for the data exchange. Writers can thus never get too far ahead of readers and also all the readers themselves are always processing the same message in parallel and wait for one-another before getting the next one.
| Modifiers | Name | Description |
|---|---|---|
private int |
parties |
| Fields inherited from class | Fields |
|---|---|
class StreamCore |
first, rest, wheneverBoundListeners |
| Constructor and description |
|---|
SyncDataflowStream
(int parties)Creates an empty stream |
SyncDataflowStream
(int parties, groovy.lang.Closure toBeApplied)Creates an empty stream while applying the supplied initialization closure to it |
private SyncDataflowStream
(int parties, java.util.Collection<MessageStream> wheneverBoundListeners, java.util.Collection<DataflowChannelListener<T>> updateListeners)Creates an empty stream with the specified listeners set |
| Type | Name and description |
|---|---|
java.lang.String |
appendingString() |
protected StreamCore<T> |
createNewStream()A factory method to create new instances of the correct class when needed |
void |
decrementParties()Decreases the number of parties required to perform the data exchange |
FList<T> |
getRest()Retrieves a DataflowStream representing the rest of this Stream after removing the first element |
void |
incrementParties()Increases the number of parties required to perform the data exchange |
private boolean |
isEmptyWithRespectToSync() |
java.lang.String |
toString() |
| Methods inherited from class | Name |
|---|---|
class StreamCore |
addUpdateListener, addUpdateListeners, appendingString, apply, bind, createNewStream, decrementParties, eos, equals, eval, filter, filter, generate, generateNext, getFirst, getFirstDFV, getRest, hashCode, hookWheneverBoundListeners, incrementParties, isEmpty, iterator, leftShift, leftShift, map, map, reduce, reduce, reduce, wheneverBound, wheneverBound |
class java.lang.Object |
java.lang.Object#wait(), java.lang.Object#wait(long, int), java.lang.Object#wait(long), java.lang.Object#equals(java.lang.Object), java.lang.Object#toString(), java.lang.Object#hashCode(), java.lang.Object#getClass(), java.lang.Object#notify(), java.lang.Object#notifyAll() |
Creates an empty stream
parties - The number of readers to ask for a value before the message gets exchanged.Creates an empty stream while applying the supplied initialization closure to it
parties - The number of readers to ask for a value before the message gets exchanged.toBeApplied - The closure to use for initializationCreates an empty stream with the specified listeners set
parties - The number of readers to ask for a value before the message gets exchanged.wheneverBoundListeners - The collection of listeners to bind to the streamA factory method to create new instances of the correct class when needed
Decreases the number of parties required to perform the data exchange
Retrieves a DataflowStream representing the rest of this Stream after removing the first element
Increases the number of parties required to perform the data exchange
Copyright © 2008–2014 Václav Pech. All Rights Reserved.