ai.grakn.kb.internal.computer

Class GraknCqlBridgeRecordReader

java.lang.Object

org.apache.hadoop.mapreduce.RecordReader<org.janusgraph.diskstorage.StaticBuffer,Iterable<org.janusgraph.diskstorage.Entry>>

ai.grakn.kb.internal.computer.GraknCqlBridgeRecordReader

All Implemented Interfaces:

Closeable, AutoCloseable

public class GraknCqlBridgeRecordReader
extends org.apache.hadoop.mapreduce.RecordReader<org.janusgraph.diskstorage.StaticBuffer,Iterable<org.janusgraph.diskstorage.Entry>>

Background: The CqlRecordReader class has changed significantly in Cassandra-3 from Cassandra-2. This class acts as a bridge between CqlRecordReader in Cassandra-2 to Cassandra-3. In essence, this class recreates CqlRecordReader from Cassandra-3 without referring to it (because otherwise we'd get functionality from CqlRecordReader on Cassandra-2 and we don't want it).

See Also:

Issue 172.

Method Summary

Modifier and Type	Method and Description
void	close()
org.janusgraph.diskstorage.StaticBuffer	getCurrentKey()
Iterable<org.janusgraph.diskstorage.Entry>	getCurrentValue()
int	getNativeProtocolVersion() Return native version protocol of the cluster connection
float	getProgress()
void	initialize(org.apache.hadoop.mapreduce.InputSplit split, org.apache.hadoop.mapreduce.TaskAttemptContext context)
boolean	nextKeyValue()

Methods inherited from class java.lang.Object

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

Method Detail

initialize

public void initialize(org.apache.hadoop.mapreduce.InputSplit split,
                       org.apache.hadoop.mapreduce.TaskAttemptContext context)
                throws IOException

Specified by:

initialize in class org.apache.hadoop.mapreduce.RecordReader<org.janusgraph.diskstorage.StaticBuffer,Iterable<org.janusgraph.diskstorage.Entry>>

Throws:

IOException

close

public void close()

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Specified by:

close in class org.apache.hadoop.mapreduce.RecordReader<org.janusgraph.diskstorage.StaticBuffer,Iterable<org.janusgraph.diskstorage.Entry>>

getCurrentKey

public org.janusgraph.diskstorage.StaticBuffer getCurrentKey()

Specified by:

getCurrentKey in class org.apache.hadoop.mapreduce.RecordReader<org.janusgraph.diskstorage.StaticBuffer,Iterable<org.janusgraph.diskstorage.Entry>>

getCurrentValue

public Iterable<org.janusgraph.diskstorage.Entry> getCurrentValue()
                                                           throws IOException

Specified by:

getCurrentValue in class org.apache.hadoop.mapreduce.RecordReader<org.janusgraph.diskstorage.StaticBuffer,Iterable<org.janusgraph.diskstorage.Entry>>

Throws:

IOException

getProgress

public float getProgress()

Specified by:

getProgress in class org.apache.hadoop.mapreduce.RecordReader<org.janusgraph.diskstorage.StaticBuffer,Iterable<org.janusgraph.diskstorage.Entry>>

nextKeyValue

public boolean nextKeyValue()
                     throws IOException

Specified by:

nextKeyValue in class org.apache.hadoop.mapreduce.RecordReader<org.janusgraph.diskstorage.StaticBuffer,Iterable<org.janusgraph.diskstorage.Entry>>

Throws:

IOException

getNativeProtocolVersion

public int getNativeProtocolVersion()

Return native version protocol of the cluster connection

Returns:

serialization protocol version.