Actually your code will not finish in cyclic graphs, consider graph 1 -> 2 -> 1. You must have some array where you can flag which node's you've visited already. And also for each node you can save previous nodes, from which you came. So here is correct code:
private Map<Node, Boolean>> vis = new HashMap<Node, Boolean>();
private Map<Node, Node> prev = new HashMap<Node, Node>();
public List getDirections(Node start, Node finish){
List directions = new LinkedList();
Queue q = new LinkedList();
Node current = start;
q.add(current);
vis.put(current, true);
while(!q.isEmpty()){
current = q.remove();
if (current.equals(finish)){
break;
}else{
for(Node node : current.getOutNodes()){
if(!vis.contains(node)){
q.add(node);
vis.put(node, true);
prev.put(node, current);
}
}
}
}
if (!current.equals(finish)){
System.out.println("can't reach destination");
}
for(Node node = finish; node != null; node = prev.get(node)) {
directions.add(node);
}
directions.reverse();
return directions;
}
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…