com.google.appengine.tools.mapreduce.impl

Class KeyValuesMarshaller<K,V>

java.lang.Object

com.google.appengine.tools.mapreduce.Marshaller<KeyValue<K,? extends Iterable<V>>>

com.google.appengine.tools.mapreduce.impl.KeyValuesMarshaller<K,V>

Type Parameters:

K - key type

V - value type

All Implemented Interfaces:

Serializable

public class KeyValuesMarshaller<K,V>
extends Marshaller<KeyValue<K,? extends Iterable<V>>>

Marshalls KeyValue pairs where the value is an iterator. Used to marshal and unmarshal data from the sort to the reducer. For internal use only. User code cannot safely depend on this class.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
KeyValuesMarshaller(Marshaller<K> keyMarshaller, Marshaller<V> valueMarshaller)

Method Summary

Methods

Modifier and Type	Method and Description
KeyValue<K,Iterable<V>>	fromBytes(ByteBuffer input) Returns the object whose serialized representation is in b between b.position() and b.limit().
ByteBuffer	toBytes(KeyValue<K,? extends Iterable<V>> keyValues) Returns a new ByteBuffer b with a serialized representation of object between b.position() and b.limit().

Methods inherited from class java.lang.Object

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

Constructor Detail

KeyValuesMarshaller

public KeyValuesMarshaller(Marshaller<K> keyMarshaller,
                   Marshaller<V> valueMarshaller)

Method Detail

toBytes

public ByteBuffer toBytes(KeyValue<K,? extends Iterable<V>> keyValues)

Description copied from class: Marshaller

Returns a new ByteBuffer b with a serialized representation of object between b.position() and b.limit(). b.order() is undefined.

Specified by:

toBytes in class Marshaller<KeyValue<K,? extends Iterable<V>>>

fromBytes

public KeyValue<K,Iterable<V>> fromBytes(ByteBuffer input)

Description copied from class: Marshaller

Returns the object whose serialized representation is in b between b.position() and b.limit(). The value of b.order() when the method is called is undefined, and this method may modify it as well as b.position() and b.limit().

The method may throw a RuntimeException if it determines that the sequence of bytes in b was not generated by Marshaller.toBytes(T). This includes corrupted data as well as trailing bytes.

Specified by:

fromBytes in class Marshaller<KeyValue<K,? extends Iterable<V>>>