org.infinispan.commons.marshall

Class AbstractExternalizer<T>

java.lang.Object

org.infinispan.commons.marshall.AbstractExternalizer<T>

All Implemented Interfaces:

java.io.Serializable, AdvancedExternalizer<T>, Externalizer<T>

Direct Known Subclasses:

ByteBufferImpl.Externalizer, Immutables.ImmutableMapWrapperExternalizer, InfinispanCollections.EmptyList.EmptyListExternalizer, InfinispanCollections.EmptyMap.EmptyMapExternalizer, InfinispanCollections.EmptySet.EmptySetExternalizer, NoStateExternalizer

public abstract class AbstractExternalizer<T>
extends java.lang.Object
implements AdvancedExternalizer<T>

Base class for AdvancedExternalizer implementations that offers default implementations for some of its methods. In particular, this base class offers a default implementation for AdvancedExternalizer.getId() that returns null which is particularly useful for advanced externalizers whose id will be provided by XML or programmatic configuration rather than the externalizer implementation itself.

Since:

5.0

Author:

Galder Zamarreño

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AbstractExternalizer()

Method Summary

Methods

Modifier and Type	Method and Description
java.lang.Integer	getId() Returns an integer that identifies the externalizer type.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.infinispan.commons.marshall.AdvancedExternalizer

getTypeClasses

Methods inherited from interface org.infinispan.commons.marshall.Externalizer

readObject, writeObject

Constructor Detail

AbstractExternalizer

public AbstractExternalizer()

Method Detail

getId

public java.lang.Integer getId()

Description copied from interface: AdvancedExternalizer

Returns an integer that identifies the externalizer type. This is used at read time to figure out which AdvancedExternalizer should read the contents of the incoming buffer. Using a positive integer allows for very efficient variable length encoding of numbers, and it's much more efficient than shipping AdvancedExternalizer implementation class information around. Negative values are not allowed. Implementers of this interface can use any positive integer as long as it does not clash with any other identifier in the system. You can find information on the pre-assigned identifier ranges in here. It's highly recommended that maintaining of these identifiers is done in a centralized way and you can do so by making annotations reference a set of statically defined identifiers in a separate class or interface. Such class/interface gives a global view of the identifiers in use and so can make it easier to assign new ids. Implementors can optionally avoid giving a meaningful implementation to this method (i.e. return null) and instead rely on XML or programmatic configuration to provide the AdvancedExternalizer id. If no id can be determined via the implementation or XML/programmatic configuration, an error will be reported. If an id has been defined both via the implementation and XML/programmatic configuration, the value defined via XML/programmatic configuration will be used ignoring the other.

Specified by:

getId in interface AdvancedExternalizer<T>

Returns:

A positive identifier for the AdvancedExternalizer.