ObjectStore Object

System administrators typically use the IBM® Administration Console for Content Platform Engine to create object stores and to expand them with addons. However, you can develop a custom application to perform these same operations.

An object store is represented by the ObjectStore class in the Content Engine API. You can use static methods on the Factory inner classes to create instances of ObjectStore. Use createInstance to create a new instance of an ObjectStore object. There is an overloaded version of createInstance for specifying a customized schema script, which allows you to get finer grained control of storage locations for object store tables, indexes, and LOB columns than you can get by using the ObjectStore object's default database storage locations.

When a new instance of an ObjectStore object is created with createInstance, the ObjectStore object does not exist in the Global Configuration Database (GCD) until a round trip to the server happens at a later commit (save) step. The save step can be an explicit call to the save method, or it can be started in a batch operation.

Use getInstance or fetchInstance to retrieve an existing instance of an ObjectStore object. The difference between these two methods is that getInstance does not verify the existence of the requested object on the server; it returns a local reference to the object, which is not affiliated with a server object until you perform a function on the object (for example, fetch a property value) that causes a round trip to the server. This technique, also called "fetchless instantiation", is useful when the wanted object serves only passively, for example, as the target value of an object-valued property. The fetchInstance method, however, immediately makes a round trip to the server to retrieve the property values of the ObjectStore object.

In addition to using Factory methods to instantiate an ObjectStore object, you can get a reference to an ObjectStore object from other objects. You can retrieve a ObjectStoreSet collection from Domain and iterate the collection. You can get a ObjectStore object from an instance of a RepositoryObject subclass.

In most cases when you are using Factory methods such as createInstance and fetchInstance to create or retrieve instances of known object types in an object store, you must specify the object store as a parameter to the method. Calling the save method on the returned object saves it in the specified object store. If you don't have prior knowledge of the object type, you can use the methods on the InstantiatingScope interface to create or retrieve objects.