org.apache.giraph.utils

Class ByteStructVertexIdDataIterator<I extends org.apache.hadoop.io.WritableComparable,T>

java.lang.Object

org.apache.giraph.utils.ByteStructVertexIdIterator<I>

org.apache.giraph.utils.ByteStructVertexIdDataIterator<I,T>

Type Parameters:

I - vertexId type parameter

T - vertexData type parameter

All Implemented Interfaces:

VertexIdDataIterator<I,T>, VertexIdIterator<I>

Direct Known Subclasses:

ByteStructVertexIdEdgeIterator, ByteStructVertexIdMessageBytesIterator, ByteStructVertexIdMessageIterator

@NotThreadSafe
public class ByteStructVertexIdDataIterator<I extends org.apache.hadoop.io.WritableComparable,T>
extends ByteStructVertexIdIterator<I>
implements VertexIdDataIterator<I,T>

Special iterator that reuses vertex ids and data objects so that the lifetime of the object is only until next() is called. Vertex id ownership can be released if desired through releaseCurrentVertexId(). This optimization allows us to cut down on the number of objects instantiated and garbage collected.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	dataSize Serialized size of the message object in bytestore
protected AbstractVertexIdData<I,T>	vertexIdData VertexIdData to iterate over

Fields inherited from class org.apache.giraph.utils.ByteStructVertexIdIterator

extendedDataInput, vertexId

Constructor Summary

Constructors

Constructor and Description
ByteStructVertexIdDataIterator(AbstractVertexIdData<I,T> vertexIdData) Constructor

Method Summary

Modifier and Type	Method and Description
T	getCurrentData() Get the current data.
int	getCurrentDataSize() Get serialized size of current data
void	next() Moves to the next element in the iteration.
T	releaseCurrentData() Release the current data object.

Methods inherited from class org.apache.giraph.utils.ByteStructVertexIdIterator

getCurrentVertexId, hasNext, releaseCurrentVertexId

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.giraph.utils.VertexIdIterator

getCurrentVertexId, hasNext, releaseCurrentVertexId

Field Detail

vertexIdData

protected AbstractVertexIdData<I extends org.apache.hadoop.io.WritableComparable,T> vertexIdData

VertexIdData to iterate over

dataSize

protected int dataSize

Serialized size of the message object in bytestore

Constructor Detail

ByteStructVertexIdDataIterator

public ByteStructVertexIdDataIterator(AbstractVertexIdData<I,T> vertexIdData)

Constructor

Parameters:

vertexIdData - vertexIdData

Method Detail

next

public void next()

Description copied from interface: VertexIdIterator

Moves to the next element in the iteration.

Specified by:

next in interface VertexIdIterator<I extends org.apache.hadoop.io.WritableComparable>

getCurrentDataSize

public int getCurrentDataSize()

Description copied from interface: VertexIdDataIterator

Get serialized size of current data

Specified by:

getCurrentDataSize in interface VertexIdDataIterator<I extends org.apache.hadoop.io.WritableComparable,T>

Returns:

serialized size of data

getCurrentData

public T getCurrentData()

Description copied from interface: VertexIdDataIterator

Get the current data.

Specified by:

getCurrentData in interface VertexIdDataIterator<I extends org.apache.hadoop.io.WritableComparable,T>

Returns:

Current data

releaseCurrentData

public T releaseCurrentData()

Description copied from interface: VertexIdDataIterator

Release the current data object.

Specified by:

releaseCurrentData in interface VertexIdDataIterator<I extends org.apache.hadoop.io.WritableComparable,T>

Returns:

Released data object