@Override
	public void update(Observable o, Object arg) {
		// do nothing
	}
This is a method provided by the {@link Observer} interface and must be 
implemented.  However, we will not be using it (see {@link InstructionTableObserver} 
for details).
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/instructionsearch/model/InstructionTableModel.java