de.hpi.fgis.voidgen.hadoop.tasks.inputstatistics
Class Task1Mapper
java.lang.Object
org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.Text,org.apache.hadoop.io.Text,org.apache.hadoop.io.NullWritable>
de.hpi.fgis.voidgen.hadoop.tasks.inputstatistics.Task1Mapper
public class Task1Mapper
- extends org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.Text,org.apache.hadoop.io.Text,org.apache.hadoop.io.NullWritable>
This Mapper reads quadruple files
where each line contains and RDF quadruple
in N-Quad format.
Outputs each single part of the quadruple.
Input
- Key: ignored
- Value: an RDF quadruple in N-Quad format
Output
- Key: subject, predicate, object and context field of the quadruple
- Value: ignored
- Author:
- Dandy Fenz, Hasso Plattner Institute at University of Potsdam, Germany, Matthias Pohl, 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 |
Field Summary |
static java.lang.String |
CONT
|
static java.lang.String |
OBJ
|
static java.lang.String |
PRED
|
static java.lang.String |
RES
|
static java.lang.String |
SUBJ
|
Method Summary |
void |
map(org.apache.hadoop.io.LongWritable key,
org.apache.hadoop.io.Text value,
org.apache.hadoop.mapreduce.Mapper.Context context)
|
Methods inherited from class org.apache.hadoop.mapreduce.Mapper |
cleanup, run, setup |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
SUBJ
public static final java.lang.String SUBJ
- See Also:
- Constant Field Values
PRED
public static final java.lang.String PRED
- See Also:
- Constant Field Values
OBJ
public static final java.lang.String OBJ
- See Also:
- Constant Field Values
CONT
public static final java.lang.String CONT
- See Also:
- Constant Field Values
RES
public static final java.lang.String RES
- See Also:
- Constant Field Values
Task1Mapper
public Task1Mapper()
map
public void map(org.apache.hadoop.io.LongWritable key,
org.apache.hadoop.io.Text value,
org.apache.hadoop.mapreduce.Mapper.Context context)
throws java.io.IOException,
java.lang.InterruptedException
- Overrides:
map
in class org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.Text,org.apache.hadoop.io.Text,org.apache.hadoop.io.NullWritable>
- Throws:
java.io.IOException
java.lang.InterruptedException