public void unregisterNode(String key) {
		
		Iterator<Entry<String, GenericNode>> it = nodes.entrySet().iterator();
		
		Iterator<GenericEdge> it2;
		
		GenericNode tmp;

		while( it.hasNext() ) {
			
			tmp = it.next().getValue();
			
			it2 = tmp.getEdges().iterator();
			
			while(it2.hasNext()) {
				if(it2.next().getOther(tmp) == getNode(key)) {
					it2.remove();
				}
			}
		}
		
		nodes.remove(key);
	}