java - Arraylist 分为 -

Question

我有一个数组列表:

ArrayList<String> allText = new ArrayList<String>();

其内容是这样的:

[Alabama - Montgomery, Alaska - Juneau, Arizona - Phoenix, Arkansas - Little Rock, California - Sacramento, Colorado - Denver]

我怎样才能将它分成2个数组列表，例如:

List<String> states = new ArrayList<>(); : [Alabama, Alaska, Arizona, Arkansas]

List<String> capitals = new ArrayList<>(); : [Montgomery, Juneau, Phoenix, Little Rock]

我有这个，但它不起作用，它给了我一个关于 allText (Scanner scanner = new Scanner(allText);) 的错误，它需要一个字符串而不是数组列表:

 Scanner scanner = new Scanner(allText);

    List<String> states = new ArrayList<>();
    List<String> capitals = new ArrayList<>();

    while (scanner.hasNextLine()) {
        String[] parts = scanner.nextLine().split(" - ");
        states.add(parts[0]);
        capitals.add(parts[1]);
    }

Answer 1

it gives me an error on allText (Scanner scanner = new Scanner(allText);) it wants a string and not an arraylist

因为您将 ArrayList 对象传递给 Scanner。但没有这样的构造函数。

Scanner

    for(String str:allText)
    {
    String[] parts = str.split(" - ");
    states.add(parts[0]);
    capitals.add(parts[1]);
    }

需要for循环来迭代allText。因为它是一个列表。