private boolean eventAreEqual(boolean ignoreMachine, Event firstEvent, Event secondEvent) {
		boolean typesEqual = firstEvent.getType().equals(secondEvent.getType());

		boolean valuesEqual = firstEvent.getValue()==null?
				secondEvent.getValue()==null :
				firstEvent.getValue().equals(secondEvent.getValue());

		boolean machinesEqual = ignoreMachine ||
				firstEvent.getMachine().equals(secondEvent.getMachine());

		return typesEqual && valuesEqual && machinesEqual;
	}