@Override
	public synchronized void close() {
		if (dbHandle.isTransactionActive()) {
			Msg.error(this, "DTM closed with active transaction",
				new RuntimeException("DTM closed with active transaction"));
		}
		undoList.clear();
		redoList.clear();
		if (!dbHandle.isClosed()) {
			dbHandle.close();
		}
		super.close();
	}
Get all transaction names that are available within the {@link #redo()} stack.

@return all transaction names that are available within the {@link #redo()} stack.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/data/StandAloneDataTypeManager.java