Package org.pipecraft.pipes.async.inter

Class SyncToAsyncPipe<T>

java.lang.Object

org.pipecraft.pipes.async.AsyncPipe<T>

org.pipecraft.pipes.async.inter.SyncToAsyncPipe<T>

All Implemented Interfaces:

Closeable, AutoCloseable, BasePipe

public class SyncToAsyncPipe<T>
extends AsyncPipe<T>

A pipe converting multiple sync pipes into a single async one. The caller can configure the number of threads used for publishing the input pipes' items. The implementation makes sure to maintain thread safety of the synchronous input pipes by handling each pipe using a single thread.

Author:

Eyal Schneider

Nested Class Summary

Nested classes/interfaces inherited from class org.pipecraft.pipes.async.AsyncPipe

AsyncPipe.Status

Constructor Summary

Constructors

Constructor	Description
SyncToAsyncPipe(Collection<PipeSupplier<T>> inputPipeSuppliers, int threadCount)	Constructor

Method Summary

Modifier and Type	Method	Description
void	close()
static <T> SyncToAsyncPipe<T>	fromPipe(Pipe<T> input)
static <T> SyncToAsyncPipe<T>	fromPipes(Collection<Pipe<T>> inputs, int threadCount)
float	getProgress()
void	start()	Performs pre-processing prior to item flow throw the pipe.

Methods inherited from class org.pipecraft.pipes.async.AsyncPipe

getStatus, notifyDone, notifyError, notifyNext, setListener

Methods inherited from class java.lang.Object

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

Constructor Detail

SyncToAsyncPipe

public SyncToAsyncPipe(Collection<PipeSupplier<T>> inputPipeSuppliers,
                       int threadCount)

Constructor

Parameters:

inputPipeSuppliers - The input pipe suppliers (allowing lazy initialization). The produced pipes are not required to be thread safe.

threadCount - The number of threads to actively fetch data from the input pipes. Thread compete on "acquiring" pipes and then draining them. There's no benefit in setting number of threads larger than the number of pipes.

Method Detail

start

public void start()
           throws PipeException,
                  InterruptedException

Description copied from interface: BasePipe

Performs pre-processing prior to item flow throw the pipe. Implementations must call the same method for all their input pipes before accessing their items. This is typically done here.

Throws:

PipeException - In case of pipe errors in this pipe or somewhere up-stream.

InterruptedException - In case that the operation has been interrupted by another thread.

getProgress

public float getProgress()

Returns:

Percent of pipes that were finished.

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class AsyncPipe<T>

Throws:

IOException

fromPipes

public static <T> SyncToAsyncPipe<T> fromPipes(Collection<Pipe<T>> inputs,
                                               int threadCount)

Parameters:

inputs - A collection of pipes to be fed into the SyncToAsyncPipe

threadCount - The number of threads to actively fetch data from the input pipes. Must not exceed the number of input pipes. Each thread is assigned an exclusive set of pipes to read from.

Returns:

A new SyncToAsyncPipe initialized with the given input pipes

fromPipe

public static <T> SyncToAsyncPipe<T> fromPipe(Pipe<T> input)

Parameters:

input - The pipe to be fed into the SyncToAsyncPipe

Returns:

A new SyncToAsyncPipe initialized with the given input pipes