groovyx.gpars.dataflow

Class SyncDataflowQueue<T>

java.lang.Object

groovyx.gpars.dataflow.DataflowQueue<T>

groovyx.gpars.dataflow.SyncDataflowQueue<T>

All Implemented Interfaces:

DataflowChannel<T>, DataflowReadChannel<T>, DataflowWriteChannel<T>, SelectableChannel<T>

public final class SyncDataflowQueue<T>
extends DataflowQueue<T>

Represents a thread-safe synchronous data flow stream. Values or DataflowVariables are added using the '<<' operator and safely read once available using the 'val' property. The iterative methods like each(), collect(), iterator(), any(), all() or the for loops work with snapshots of the stream at the time of calling the particular method. For actors and Dataflow Operators the asynchronous non-blocking variants of the getValAsync() methods can be used. They register the request to read a value and will send a message to the actor or operator once the value is available.

Unlike DataflowQueue, which exchanges data asynchronously, SyncDataflowQueue blocks the writer until a reader is ready to consume the message.

Author:

Vaclav Pech Date: Jun 5, 2009

Constructor Summary

Constructors

Constructor and Description
SyncDataflowQueue()

Method Summary

Methods

Modifier and Type	Method and Description
<V> DataflowReadChannel<V>	chainWith(PGroup group, groovy.lang.Closure<V> closure) Creates and attaches a new operator processing values from the channel
protected DataflowVariable<T>	createVariable() Creates a new variable to perform the next data exchange
<V> DataflowReadChannel<V>	merge(PGroup group, java.util.List<DataflowReadChannel<java.lang.Object>> others, groovy.lang.Closure<V> closure) Merges channels together as inputs for a single dataflow operator.
DataflowReadChannel<T>	tap(PGroup group, DataflowWriteChannel<T> target) Taps into the pipeline.
java.lang.String	toString()

Methods inherited from class groovyx.gpars.dataflow.DataflowQueue

binaryChoice, binaryChoice, binaryChoice, binaryChoice, binaryChoice, binaryChoice, bind, chainWith, chainWith, chainWith, chainWith, chainWith, choice, choice, choice, choice, choice, choice, filter, filter, filter, filter, filter, filter, getEventManager, getQueue, getVal, getVal, getValAsync, getValAsync, into, into, into, into, into, into, isBound, iterator, leftShift, leftShift, length, merge, merge, merge, merge, merge, merge, merge, merge, merge, merge, merge, or, or, poll, rightShift, separate, separate, separate, separate, separate, separate, split, split, split, split, split, split, split, split, split, split, split, split, tap, tap, tap, tap, tap, then, then, then, whenBound, whenBound, whenBound, whenBound, wheneverBound, wheneverBound

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

SyncDataflowQueue

public SyncDataflowQueue()

Method Detail

createVariable

protected DataflowVariable<T> createVariable()

Creates a new variable to perform the next data exchange

Overrides:

createVariable in class DataflowQueue<T>

Returns:

The newly created SyncDataflowVariable instance with exactly one expected reader

chainWith

public <V> DataflowReadChannel<V> chainWith(PGroup group,
                                   groovy.lang.Closure<V> closure)

Description copied from interface: DataflowReadChannel

Creates and attaches a new operator processing values from the channel

Specified by:

chainWith in interface DataflowReadChannel<T>

Overrides:

chainWith in class DataflowQueue<T>

Type Parameters:

V - The type of values returned from the supplied closure

Parameters:

group - The PGroup to use

closure - The function to invoke on all incoming values as part of the new operator's body

Returns:

A channel of the same type as this channel, which the new operator will output into.

tap

public DataflowReadChannel<T> tap(PGroup group,
                         DataflowWriteChannel<T> target)

Description copied from interface: DataflowReadChannel

Taps into the pipeline. The supplied channel will receive a copy of all messages passed through.

Specified by:

tap in interface DataflowReadChannel<T>

Overrides:

tap in class DataflowQueue<T>

Parameters:

group - The PGroup to use

target - The channel to tap data into

Returns:

A channel of the same type as this channel, which the new operator will output into.

merge

public <V> DataflowReadChannel<V> merge(PGroup group,
                               java.util.List<DataflowReadChannel<java.lang.Object>> others,
                               groovy.lang.Closure<V> closure)

Description copied from interface: DataflowReadChannel

Merges channels together as inputs for a single dataflow operator.

Specified by:

merge in interface DataflowReadChannel<T>

Overrides:

merge in class DataflowQueue<T>

Type Parameters:

V - The type of values passed between the channels

Parameters:

group - The PGroup to use

others - The channels to merge with

closure - The function to invoke on all incoming values as part of the new operator's body. The number of arguments to the closure must match the number of input channels.

Returns:

A channel of the same type as this channel, which the new operator will output into.

toString

public java.lang.String toString()

Overrides:

toString in class DataflowQueue<T>