Package com.esotericsoftware.kryo.serializers

Class CollectionSerializer<T extends Collection>

java.lang.Object

com.esotericsoftware.kryo.Serializer<T>

com.esotericsoftware.kryo.serializers.CollectionSerializer<T>

Direct Known Subclasses:

DefaultSerializers.ArraysAsListSerializer, DefaultSerializers.PriorityQueueSerializer, DefaultSerializers.TreeSetSerializer, ImmutableCollectionsSerializers.JdkImmutableListSerializer, ImmutableCollectionsSerializers.JdkImmutableSetSerializer

public class CollectionSerializer<T extends Collection>
extends Serializer<T>

Serializes objects that implement the Collection interface.

With the default constructor, a collection requires a 1-3 byte header and an extra 2-3 bytes is written for each element in the collection.

Author:

Nathan Sweet

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	CollectionSerializer.BindCollection	Annotates a Collection field with CollectionSerializer settings for FieldSerializer.

Constructor Summary

Constructors

Constructor	Description
CollectionSerializer()

Method Summary

Modifier and Type	Method	Description
T	copy(Kryo kryo, T original)	Returns a copy of the specified object.
protected T	create(Kryo kryo, Input input, Class<? extends T> type, int size)	Used by read(Kryo, Input, Class) to create the new object.
protected T	createCopy(Kryo kryo, T original)	Used by copy(Kryo, Collection) to create the new object.
Class	getElementClass()
Serializer	getElementSerializer()
T	read(Kryo kryo, Input input, Class<? extends T> type)	Reads bytes and returns a new object of the specified concrete type.
void	setElementClass(Class elementClass)	The concrete class of the collection elements, or null if it is not known.
void	setElementClass(Class elementClass, Serializer serializer)	Sets both setElementClass(Class) and setElementSerializer(Serializer).
void	setElementsCanBeNull(boolean elementsCanBeNull)
void	setElementSerializer(Serializer elementSerializer)	The serializer to be used for elements in collection, or null to use the serializer registered with Kryo for each element's type.
void	write(Kryo kryo, Output output, T collection)	Writes the bytes for the object to the output.
protected void	writeHeader(Kryo kryo, Output output, T collection)	Can be overidden to write data needed for create(Kryo, Input, Class, int).

Methods inherited from class com.esotericsoftware.kryo.Serializer

getAcceptsNull, isImmutable, setAcceptsNull, setImmutable

Methods inherited from class java.lang.Object

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

Constructor Detail

CollectionSerializer

public CollectionSerializer()

Method Detail

setElementsCanBeNull

public void setElementsCanBeNull(boolean elementsCanBeNull)

Parameters:

elementsCanBeNull - False if all elements are not null. This saves 1 byte per element if elementClass is set. True if it is not known (default).

setElementClass

public void setElementClass(Class elementClass)

The concrete class of the collection elements, or null if it is not known. This saves 1-2 bytes per element. Only set to a non-null value if the elements in the collection are known to all be instances of this class (or null).

getElementClass

public Class getElementClass()

setElementClass

public void setElementClass(Class elementClass,
                            Serializer serializer)

Sets both setElementClass(Class) and setElementSerializer(Serializer).

setElementSerializer

public void setElementSerializer(Serializer elementSerializer)

The serializer to be used for elements in collection, or null to use the serializer registered with Kryo for each element's type. Default is null.

getElementSerializer

public Serializer getElementSerializer()

write

public void write(Kryo kryo,
                  Output output,
                  T collection)

Description copied from class: Serializer

Writes the bytes for the object to the output.

This method should not be called directly, instead this serializer can be passed to Kryo write methods that accept a serialier.

Specified by:

write in class Serializer<T extends Collection>

collection - May be null if Serializer.getAcceptsNull() is true.

writeHeader

protected void writeHeader(Kryo kryo,
                           Output output,
                           T collection)

Can be overidden to write data needed for create(Kryo, Input, Class, int). The default implementation does nothing.

create

protected T create(Kryo kryo,
                   Input input,
                   Class<? extends T> type,
                   int size)

Used by read(Kryo, Input, Class) to create the new object. This can be overridden to customize object creation (eg to call a constructor with arguments), optionally reading bytes written in writeHeader(Kryo, Output, Collection). The default implementation uses Kryo.newInstance(Class) with special cases for ArrayList and HashSet.

read

public T read(Kryo kryo,
              Input input,
              Class<? extends T> type)

Description copied from class: Serializer

Reads bytes and returns a new object of the specified concrete type.

Before Kryo can be used to read child objects, Kryo.reference(Object) must be called with the parent object to ensure it can be referenced by the child objects. Any serializer that uses Kryo to read a child object may need to be reentrant.

This method should not be called directly, instead this serializer can be passed to Kryo read methods that accept a serialier.

Specified by:

read in class Serializer<T extends Collection>

Returns:

May be null if Serializer.getAcceptsNull() is true.

createCopy

protected T createCopy(Kryo kryo,
                       T original)

Used by copy(Kryo, Collection) to create the new object. This can be overridden to customize object creation, eg to call a constructor with arguments. The default implementation uses Kryo.newInstance(Class).

copy

public T copy(Kryo kryo,
              T original)

Description copied from class: Serializer

Returns a copy of the specified object. The default implementation returns the original if Serializer.isImmutable() is true, else throws KryoException. Subclasses can optionall override this method to support Kryo.copy(Object).

Before Kryo can be used to copy child objects, Kryo.reference(Object) must be called with the copy to ensure it can be referenced by the child objects. A serializer that uses Kryo to copy a child object may need to be reentrant.

This method should not be called directly, instead this serializer can be passed to Kryo copy methods that accept a serialier.

Overrides:

copy in class Serializer<T extends Collection>