The Id OSID provides the means for creating and mapping identifiers. All OSID objects are identified by a unique and immutable Id. The Id OSID can be used to generate new Ids when creating new objects.

Consumers wishing to persist an OSID object should instead persist the reference to the object by serializing the Id.

Most OSID interfaces are used to encapsulate implementation-specific objects from provider to consumer. Id is an OsidPrimitive and as such cannot be used to encapsulate implementation-specific data other than what is defined explicitly in the Id. An OSID Provider must respect any Id based on its interface alone.

The Id service can be used to assign Ids for an OSID Provider or be used to manage Id translations for system to system compatibility.

The Id service can also be used as a means to map one identifier to another when an object is known by multiple identifiers. Mapping identifier spaces is often a critical part of interoperability and the Id service can be used as a shim to bridge different systems.

Id Mapping Example

                         
                         
                         public Asset getAsset(assetId) {
                             Id id = idSession.getId(assetId);
                             return (other_impl.getAsset(assetId));
                         }