VTAssociationDB getAssociation(long associationKey) {
		try {
			lock.acquire();
			VTAssociationDB associationDB = associationCache.get(associationKey);
			if (associationDB != null) {
				return associationDB;
			}
			DBRecord record = associationTableAdapter.getRecord(associationKey);
			if (record == null) {
				return null;
			}
			return new VTAssociationDB(this, associationCache, record);
		}
		catch (IOException e) {
			session.dbError(e);
		}
		finally {
			lock.release();
		}
		return null;
	}
Called when an existing session has been initialized with its programs.  This is not called
when a new session is created.
Ghidra/Features/VersionTracking/src/main/java/ghidra/feature/vt/api/db/AssociationDatabaseManager.java