com.triactive.jdo.store
Class OIDGenerator

java.lang.Object
  com.triactive.jdo.store.OIDGenerator

Direct Known Subclasses:

DatastoreOIDGenerator, NondurableOIDGenerator

public abstract class OIDGenerator

extends java.lang.Object

Generates OIDs for a single class of objects.

Author:

Mike Martin

Field Summary

protected short	classId The class ID of OIDs to generate.
protected int	nextHiValue The hi value of the next OID to be returned.
protected short	nextLoValue The lo value of the next OID to be returned.

Constructor Summary

OIDGenerator(int classId)
Constructs a new OID generator.

Method Summary

OID	maximum() Returns the highest possible OID value for the class of OIDs returned by this generator.
OID	minimum() Returns the lowest possible OID value for the class of OIDs returned by this generator.
abstract OID	next(StoreManager storeMgr) Generates the next unique OID value.

Methods inherited from class java.lang.Object

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

Field Detail

classId

protected final short classId

The class ID of OIDs to generate.

nextHiValue

protected int nextHiValue

The hi value of the next OID to be returned.

nextLoValue

protected short nextLoValue

The lo value of the next OID to be returned.

Constructor Detail

OIDGenerator

public OIDGenerator(int classId)

Constructs a new OID generator.

Parameters:

classId - the class ID of OIDs to generate.

Method Detail

minimum

public final OID minimum()

Returns the lowest possible OID value for the class of OIDs returned by this generator.

maximum

public final OID maximum()

Returns the highest possible OID value for the class of OIDs returned by this generator.

next

public abstract OID next(StoreManager storeMgr)
                  throws OIDOverflowException

Generates the next unique OID value.

Parameters:

storeMgr - the store manager to use for accessing datastore-based sequence(s), if necessary.

Returns:

the next unique OID

Throws:

OIDOverflowException - if the generator can produce no more values