Question

我使用ListIterator迭代某个对象的列表。目标是编辑列表的内容。

以下是我正在做的事情的一个例子：

public class Test {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {

        ArrayList list = new ArrayList<>(Arrays.asList("One", "Two", "Three","Four","Five"));
        ListIterator<String> listIterator = list.listIterator();
        String current ;
        while (listIterator.hasNext()) {
            doSomething(listIterator); 
            current = listIterator.next();
            //here I Want that current has the same value  as it was Before The doSomething Call
            //or in other Word , i want to save the adress of the last visired object In the List before doSomething Call.
    //As a result i can iterate from this point in the List.
            }

        }

    private static ListIterator<String> doSomething(ListIterator<String> listIterator) {
        System.out.println("Dosomething " + listIterator.next()); //
        System.out.println("Dosomething " + listIterator.next()); //
        System.out.println("Dosomething " + listIterator.next()); //
        System.out.println("Dosomething " + listIterator.next()); //
        return listIterator;
    }
}

你能不能给我一些见解？

我正在使用ListIterator因为我想要在列表中前后退出并进行编辑。

Answer 1

ListIterator会跟踪当前索引，因此您可以在致电doSomething后保存并快退：

int pos = listIterator.nextIndex();
doSomething(listIterator);
while (listIterator.nextIndex() > pos) {
    listIterator.previous();
}

这假设doSomething只推进迭代器。

如何使用ListIterator编辑列表内容

1 个答案: