com.google.appengine.tools.mapreduce

Class Marshaller<T>

java.lang.Object

com.google.appengine.tools.mapreduce.Marshaller<T>

Type Parameters:

T - type to be marshalled or unmarshalled

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

BigQueryMarshaller, KeyValueMarshaller, KeyValuesMarshaller

public abstract class Marshaller<T>
extends Object
implements Serializable

Turns objects of type T into bytes and back.

Author:

ohler@google.com (Christian Ohler)

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Marshaller()

Method Summary

Methods

Modifier and Type	Method and Description
abstract T	fromBytes(ByteBuffer b) Returns the object whose serialized representation is in b between b.position() and b.limit().
abstract ByteBuffer	toBytes(T object) 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

Marshaller

public Marshaller()

Method Detail

toBytes

public abstract ByteBuffer toBytes(T object)

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

fromBytes

public abstract T fromBytes(ByteBuffer b)

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 toBytes(T). This includes corrupted data as well as trailing bytes.