@Override
	public void close() {
		if (openCount.decrementAndGet() == 0) {
			fidFile.closingFidDB(this);

			try {
				if (openForUpdate) {
					handle.endTransaction(openTransaction, true);
				}
				handle.close();
			}
			catch (IOException e) {
				Msg.error(this, "Error closing " + this, e);
			}
			librariesTable = null;
			stringsTable = null;
			functionsTable = null;
			relationsTable = null;
		}
	}
Indicates that the user of this FidDB no longer needs it open.  This will decrement the
"open count" and if the "open count is 0, the database will be closed.
Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/db/FidDB.java