oracle.jbo.mom
Class DefinitionContext

java.lang.Object
oracle.jbo.mom.DefinitionContext

Direct Known Subclasses:

DefinitionContextStandard

public abstract class DefinitionContext

extends java.lang.Object

This abstract class encapsulates the thread-specific behavior and state needed by the DefinitionManager class.

The thread-specific behavior and state can be subdivided into two pieces: a MOM (MetaObject Manager) cache and a MOM parser.

The MOM cache maps metaobject names into metaobjects. Subclasses may optionally support ageing out ("retiring") of least-recently-used metaobjects. A retired cache entry typically retains a weak reference to the metaobject.

The MOM parser supports reading and parsing metaobject documents from a store of some sort. (Different subclasses may support different sorts of stores).

Each DefinitionManager instance will have a set of associated DefinitionContext instances, one per active client thread. In some cases, a single DefinitionContext instance can be shared by multiple threads that are running the same application.

In general, the methods on this class and its subclasses are thread-safe.

Method Summary

void	retireLeastRecentlyUsed(int numToRetire) Retires the specified number of least recently used non-retired ageable metaobjects in the MOM cache.

Methods inherited from class java.lang.Object

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

Method Detail

retireLeastRecentlyUsed

public void retireLeastRecentlyUsed(int numToRetire)

Retires the specified number of least recently used non-retired ageable metaobjects in the MOM cache. If the MOM cache contains fewer non-retired ageable metaobjects than the specified number, then all ageable metaobjects will be retired. This method is a no-op in a subclass which does not support ageing.