java - ConcurrentModificationException 和 HashSet.iterator()

Question

我有一个for循环

      for (int neighbour : neighbours) {

我可以在循环中修改 neighbors 的地方。发现这就是 ConcurrentModificationException 的原因。并阅读 https://stackoverflow.com/a/8189527/292291

Hence if you want to modify the list (or any collection in general), use iterator, because then it is aware of the modifications and hence those will be handled properly.

所以我尝试了:

neighboursItr = neighbours.iterator();
while (neighboursItr.hasNext()) {
  // try disconnecting vertices
  neighbour = neighboursItr.next();

但这并不能解决问题。为什么？

Answer 1

你是在调用 neighbours.remove(neighbor) 吗？在那种情况下，这就是问题所在。您需要改为调用 neightboursItr.remove()。