|
||||||||||
| PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
| SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD | |||||||||
java.lang.Objectorg.apache.hadoop.mapreduce.RecordReader<K,V>
org.apache.hadoop.mapreduce.lib.input.CombineFileRecordReader<K,V>
@InterfaceAudience.Public @InterfaceStability.Stable public class CombineFileRecordReader<K,V>
A generic RecordReader that can hand out different recordReaders
for each chunk in a CombineFileSplit.
A CombineFileSplit can combine data chunks from multiple files.
This class allows using different RecordReaders for processing
these data chunks from different files.
CombineFileSplit| Field Summary | |
|---|---|
protected TaskAttemptContext |
context
|
protected RecordReader<K,V> |
curReader
|
protected FileSystem |
fs
|
protected int |
idx
|
protected long |
progress
|
protected Class<? extends RecordReader<K,V>> |
rrClass
|
protected Constructor<? extends RecordReader<K,V>> |
rrConstructor
|
protected CombineFileSplit |
split
|
| Constructor Summary | |
|---|---|
CombineFileRecordReader(CombineFileSplit split,
TaskAttemptContext context,
Class<? extends RecordReader<K,V>> rrClass)
A generic RecordReader that can hand out different recordReaders for each chunk in the CombineFileSplit. |
|
| Method Summary | |
|---|---|
void |
close()
Close the record reader. |
K |
getCurrentKey()
Get the current key |
V |
getCurrentValue()
Get the current value. |
float |
getProgress()
return progress based on the amount of data processed so far. |
void |
initialize(InputSplit split,
TaskAttemptContext context)
Called once at initialization. |
protected boolean |
initNextRecordReader()
Get the record reader for the next chunk in this CombineFileSplit. |
boolean |
nextKeyValue()
Read the next key, value pair. |
| Methods inherited from class java.lang.Object |
|---|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
| Field Detail |
|---|
protected CombineFileSplit split
protected Class<? extends RecordReader<K,V>> rrClass
protected Constructor<? extends RecordReader<K,V>> rrConstructor
protected FileSystem fs
protected TaskAttemptContext context
protected int idx
protected long progress
protected RecordReader<K,V> curReader
| Constructor Detail |
|---|
public CombineFileRecordReader(CombineFileSplit split,
TaskAttemptContext context,
Class<? extends RecordReader<K,V>> rrClass)
throws IOException
IOException| Method Detail |
|---|
public void initialize(InputSplit split,
TaskAttemptContext context)
throws IOException,
InterruptedException
RecordReader
initialize in class RecordReader<K,V>split - the split that defines the range of records to readcontext - the information about the task
IOException
InterruptedException
public boolean nextKeyValue()
throws IOException,
InterruptedException
RecordReader
nextKeyValue in class RecordReader<K,V>IOException
InterruptedException
public K getCurrentKey()
throws IOException,
InterruptedException
RecordReader
getCurrentKey in class RecordReader<K,V>IOException
InterruptedException
public V getCurrentValue()
throws IOException,
InterruptedException
RecordReader
getCurrentValue in class RecordReader<K,V>IOException
InterruptedException
public void close()
throws IOException
RecordReader
close in interface Closeableclose in class RecordReader<K,V>IOException
public float getProgress()
throws IOException,
InterruptedException
getProgress in class RecordReader<K,V>IOException
InterruptedException
protected boolean initNextRecordReader()
throws IOException
IOException
|
||||||||||
| PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
| SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD | |||||||||