在游戏中我有一个玩家列表,让我们这样说:
LinkedList<String> players = new LinkedList<String>();
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我想让每个玩家与其他玩家互动,所以我写了两个嵌套循环:
Iterator<String> i1 = players.iterator();
while (i1.hasNext()) {
String p1 = i1.next();
Iterator<String> i2 = players.iterator();
// But I want to do this: Iterator<String> i2 = i1.clone();
while (i2.hasNext()) {
String p2 = i2.next();
System.out.println("Interact: " + p1 + ", " + p2);
}
}
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由于我只希望每对玩家互动一次,我想在外圈的当前玩家之后用玩家开始内循环.所以我想克隆迭代器,但是不能编译.
那么,我该怎么做呢?
NPE*_*NPE 26
以下将这样做:
ListIterator<String> i1 = players.listIterator(0);
while (i1.hasNext()) {
String p1 = i1.next();
ListIterator<String> i2 = players.listIterator(i1.nextIndex());
while (i2.hasNext()) {
String p2 = i2.next();
System.out.println("Interact: " + p1 + ", " + p2);
}
}
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它依赖于ListIterator
从给定位置开始并且也知道其当前位置的能力.