net.walend.lyophil
Interface Frozen

public interface Frozen

An optional interface for the back-end storage peers. If each Freezable objects all corrispond with an object on the back-end, then this interface can help. All methods throw RemoteExceptions due to EJB's bad habits.

Since:

20001125

Author:

David Walend

Method Summary

void	freezeFreezable(Freezable object) Puts the Freezable in cold storage.
java.io.Serializable	getIdentifier() Get the identifier for this instance.
boolean	isFrozenAvailable()
boolean	representedBy(Freezable object) Returns true if this Frozen is represented by the Freezable object.
Freezable	thawFreezable() Gets a Freezable out of cold storage.
void	throwOut() Remove a frozen instance from cold storage

Method Detail

getIdentifier

public java.io.Serializable getIdentifier()
                                   throws java.rmi.RemoteException

Get the identifier for this instance. I've always used a Long, but the ejb spec says it can be anything. Try to use something immutable. Note that you will only have this Object plus metadetails of the class to use for identifier information. All you should need is the identifier.

isFrozenAvailable

public boolean isFrozenAvailable()
                          throws java.rmi.RemoteException

freezeFreezable

public void freezeFreezable(Freezable object)
                     throws java.rmi.RemoteException

Puts the Freezable in cold storage.

Throws:

MismatchedIdentifierException - if the Freezable's identifier doesn't match this object's.

CannotFreezeException - if the Freezable can't be frozen for another reason

java.rmi.RemoteException

thawFreezable

public Freezable thawFreezable()
                        throws java.rmi.RemoteException

Gets a Freezable out of cold storage. Normally, this should be a new instance of a previously frozen Freezable.

Throws:

CannotThawException

java.rmi.RemoteException

throwOut

public void throwOut()
              throws java.rmi.RemoteException

Remove a frozen instance from cold storage

Throws:

CannotThrowOutException

java.rmi.RemoteException

representedBy

public boolean representedBy(Freezable object)
                      throws java.rmi.RemoteException

Returns true if this Frozen is represented by the Freezable object.