de.hpi.fgis.voidgen.hadoop.tasks.ksimilarity
Class KSimStep2Mapper
java.lang.Object
org.apache.hadoop.mapreduce.Mapper<StringStringPair,StringStringPair,StringArrayWritableComparable,org.apache.hadoop.io.IntWritable>
de.hpi.fgis.voidgen.hadoop.tasks.ksimilarity.KSimStep2Mapper
public class KSimStep2Mapper
- extends org.apache.hadoop.mapreduce.Mapper<StringStringPair,StringStringPair,StringArrayWritableComparable,org.apache.hadoop.io.IntWritable>
Aggregates via map-side join
all subjects sharing the same
predicate-object pair.
Emits each connected pair of subjects (cross
product of the subjects sharing the same
predicate-object pair)
The map input data is prepared as necessary
for a map-side join.
Input
- Key: the pair of
predicate and
object of the quadruple
- Value: the pair of
subject and
context of the quadruple
Output
- Key: a set of strings describing the connectedness
of two subjects (in detail subject-context pairs)
because of sharing the same predicate-object pair.
- Value: a '1' indicating that there is
one connection between both subjects.
- Author:
- Eyk Kny, Hasso Plattner Institute at University of Potsdam, Germany, Johannes Gosda, Hasso Plattner Institute at University of Potsdam, Germany
Nested classes/interfaces inherited from class org.apache.hadoop.mapreduce.Mapper |
org.apache.hadoop.mapreduce.Mapper.Context |
Methods inherited from class org.apache.hadoop.mapreduce.Mapper |
cleanup, run |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
KSimStep2Mapper
public KSimStep2Mapper()
setup
public void setup(org.apache.hadoop.mapreduce.Mapper.Context context)
- Overrides:
setup
in class org.apache.hadoop.mapreduce.Mapper<StringStringPair,StringStringPair,StringArrayWritableComparable,org.apache.hadoop.io.IntWritable>
map
protected void map(StringStringPair key,
StringStringPair value,
org.apache.hadoop.mapreduce.Mapper.Context context)
throws java.io.IOException,
java.lang.InterruptedException
- Overrides:
map
in class org.apache.hadoop.mapreduce.Mapper<StringStringPair,StringStringPair,StringArrayWritableComparable,org.apache.hadoop.io.IntWritable>
- Throws:
java.io.IOException
java.lang.InterruptedException