com.scaleoutsoftware.soss.hserver.interop

Class DataGridChunkedCollectionReader<K,V>

java.lang.Object

com.scaleoutsoftware.soss.hserver.interop.KeyValueProducer<KEY,VALUE>

com.scaleoutsoftware.soss.hserver.interop.ChunkedCollectionReader<K,Iterable<V>,com.scaleoutsoftware.soss.hserver.interop.ChunkDescriptor>

com.scaleoutsoftware.soss.hserver.interop.DataGridChunkedCollectionReader<K,V>

Type Parameters:

K - key type

V - value type

public class DataGridChunkedCollectionReader<K,V>
extends ChunkedCollectionReader<K,Iterable<V>,com.scaleoutsoftware.soss.hserver.interop.ChunkDescriptor>

A ChunkedCollectionReader implementation used by a reducer to read key-value chunks.

Method Summary

Modifier and Type	Method and Description
static <KEY,VALUE> DataGridChunkedCollectionReader<KEY,VALUE>	getGridReader(DataGridReaderParameters params) Instantiates a grid reader with the specified DataGridReaderParameters.
K	getKey() Gets the current key.
Iterable<V>	getValue() Gets the current value.
void	prepareChunk(com.scaleoutsoftware.soss.hserver.interop.ChunkDescriptor chunkDescriptor, DataInputStream dataInput, ByteBuffer buffer, int chunkIndex) This method is called once before the chunk is served.
boolean	readNext() Reads the next entry from the chunks.
Future<Object>	scheduleAsyncRead(Callable<Object> readOperation)

Methods inherited from class com.scaleoutsoftware.soss.hserver.interop.ChunkedCollectionReader

getMaxWaitingTime, getTotalWaitingTime, startReading

Methods inherited from class java.lang.Object

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

Method Detail

scheduleAsyncRead

public Future<Object> scheduleAsyncRead(Callable<Object> readOperation)

prepareChunk

public void prepareChunk(com.scaleoutsoftware.soss.hserver.interop.ChunkDescriptor chunkDescriptor,
                         DataInputStream dataInput,
                         ByteBuffer buffer,
                         int chunkIndex)
                  throws IOException

Description copied from class: ChunkedCollectionReader

This method is called once before the chunk is served. It can be used to verify the chunk header, for example.

Overrides:

prepareChunk in class ChunkedCollectionReader<K,Iterable<V>,com.scaleoutsoftware.soss.hserver.interop.ChunkDescriptor>

Parameters:

chunkDescriptor - Chunk identifier

dataInput - A DataInputStream view of the chunk

buffer - A ByteBuffer view of the chunk

chunkIndex - The index of the chunk in the chunk sequence

Throws:

IOException - If a reading error occurred

readNext

public boolean readNext()
                 throws IOException,
                        TimeoutException

Description copied from class: ChunkedCollectionReader

Reads the next entry from the chunks.

Overrides:

readNext in class ChunkedCollectionReader<K,Iterable<V>,com.scaleoutsoftware.soss.hserver.interop.ChunkDescriptor>

Returns:

true if the object was read successfully, false if there are no more objects to be read.

Throws:

IOException - if there was a ScaleOut hServer access error

TimeoutException - if the read timed out

getKey

public K getKey()

Description copied from class: ChunkedCollectionReader

Gets the current key. To switch to next key-value entry, call ChunkedCollectionReader.readNext().

Specified by:

getKey in class ChunkedCollectionReader<K,Iterable<V>,com.scaleoutsoftware.soss.hserver.interop.ChunkDescriptor>

Returns:

key object

getValue

public Iterable<V> getValue()

Description copied from class: ChunkedCollectionReader

Gets the current value. To switch to next key-value entry, call ChunkedCollectionReader.readNext().

Specified by:

getValue in class ChunkedCollectionReader<K,Iterable<V>,com.scaleoutsoftware.soss.hserver.interop.ChunkDescriptor>

Returns:

value object

getGridReader

public static <KEY,VALUE> DataGridChunkedCollectionReader<KEY,VALUE> getGridReader(DataGridReaderParameters params)
                                                                            throws IOException

Instantiates a grid reader with the specified DataGridReaderParameters.

Type Parameters:

KEY - Key type

VALUE - Value type

Parameters:

params - Parameters for a data grid reader.

Returns:

An initialized DataGridChunckedCollectionReader

Throws:

IOException - If a read error occurred.