Package | Description |
---|---|
org.apache.hadoop.mapreduce | |
org.apache.hadoop.mapreduce.lib.output | |
org.apache.hadoop.mapreduce.lib.partition |
Modifier and Type | Method and Description |
---|---|
Class<? extends Partitioner<?,?>> |
JobContext.getPartitionerClass()
Get the
Partitioner class for the job. |
Modifier and Type | Method and Description |
---|---|
void |
Job.setPartitionerClass(Class<? extends Partitioner> cls)
Set the
Partitioner for the job. |
Modifier and Type | Method and Description |
---|---|
static <K extends WritableComparable<?>,V extends Writable> |
MapFileOutputFormat.getEntry(org.apache.hadoop.io.MapFile.Reader[] readers,
Partitioner<K,V> partitioner,
K key,
V value)
Get an entry from output generated by this class.
|
Modifier and Type | Class and Description |
---|---|
class |
BinaryPartitioner<V>
Partition
BinaryComparable keys using a configurable part of
the bytes array returned by BinaryComparable.getBytes() . |
class |
HashPartitioner<K,V>
Partition keys by their
Object.hashCode() . |
class |
KeyFieldBasedPartitioner<K2,V2>
Defines a way to partition keys based on certain key fields (also see
KeyFieldBasedComparator . |
class |
RehashPartitioner<K,V>
This partitioner rehashes values returned by
Object.hashCode()
to get smoother distribution between partitions which may improve
reduce reduce time in some cases and should harm things in no cases. |
class |
TotalOrderPartitioner<K,V>
Partitioner effecting a total order by reading split points from
an externally generated source.
|
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