private Db4objects.Db4o.Ext.Db4oDatabase Query(Transaction trans, bool constrainByUUID
)
{
ObjectContainerBase stream = trans.Container();
IQuery q = stream.Query(trans);
q.Constrain(GetType());
if (constrainByUUID)
{
q.Descend(CreationtimeField).Constrain(i_uuid);
}
IObjectSet objectSet = q.Execute();
while (objectSet.HasNext())
{
Db4objects.Db4o.Ext.Db4oDatabase storedDatabase = (Db4objects.Db4o.Ext.Db4oDatabase
)objectSet.Next();
stream.Activate(null, storedDatabase, new FixedActivationDepth(4));
if (storedDatabase.Equals(this))
{
return(storedDatabase);
}
}
return(null);
}
/// <summary>make sure this Db4oDatabase is stored.</summary>
/// <remarks>make sure this Db4oDatabase is stored. Return the ID.</remarks>
public virtual int Bind(Transaction trans)
{
ObjectContainerBase stream = trans.Container();
Db4objects.Db4o.Ext.Db4oDatabase stored = (Db4objects.Db4o.Ext.Db4oDatabase)stream
.Db4oTypeStored(trans, this);
if (stored == null)
{
return(StoreAndGetId(trans));
}
if (stored == this)
{
return(stream.GetID(trans, this));
}
if (i_uuid == 0)
{
i_uuid = stored.i_uuid;
}
stream.ShowInternalClasses(true);
try
{
int id = stream.GetID(trans, stored);
stream.Bind(trans, this, id);
return(id);
}
finally
{
stream.ShowInternalClasses(false);
}
}
public virtual bool IsOlderThan(Db4objects.Db4o.Ext.Db4oDatabase peer)
{
if (peer == this)
{
throw new ArgumentException();
}
if (i_uuid != peer.i_uuid)
{
return(i_uuid < peer.i_uuid);
}
// the above logic has failed, both are the same
// age but we still want to distinguish in some
// way, to have an order in the ReplicationRecord
// The following is arbitrary, it only needs to
// be repeatable.
// Let's distinguish by signature length
if (i_signature.Length != peer.i_signature.Length)
{
return(i_signature.Length < peer.i_signature.Length);
}
for (int i = 0; i < i_signature.Length; i++)
{
if (i_signature[i] != peer.i_signature[i])
{
return(i_signature[i] < peer.i_signature[i]);
}
}
// This should never happen.
// FIXME: Add a message and move to Messages.
//
throw new Exception();
}
/// <summary>find a Db4oDatabase with the same signature as this one</summary>
public virtual Db4objects.Db4o.Ext.Db4oDatabase Query(Transaction trans)
{
// showInternalClasses(true); has to be set for this method to be successful
if (i_uuid > 0)
{
// try fast query over uuid (creation time) first
Db4objects.Db4o.Ext.Db4oDatabase res = Query(trans, true);
if (res != null)
{
return(res);
}
}
// if not found, try to find with signature
return(Query(trans, false));
}
/// <summary>comparison by signature.</summary>
/// <remarks>comparison by signature.</remarks>
public override bool Equals(object obj)
{
if (obj == this)
{
return(true);
}
if (obj == null || this.GetType() != obj.GetType())
{
return(false);
}
Db4objects.Db4o.Ext.Db4oDatabase other = (Db4objects.Db4o.Ext.Db4oDatabase)obj;
if (null == other.i_signature || null == this.i_signature)
{
return(false);
}
return(Arrays4.Equals(other.i_signature, this.i_signature));
}