如何在Java中使用迭代器？

// Java code to illustrate the use of iterator
import java.io.*;
import java.util.*;
class Test {
    public static void main(String[] args)
    {
        ArrayList<String> list = new ArrayList<String>();
        list.add("A");
        list.add("B");
        list.add("C");
        list.add("D");
        list.add("E");
        // Iterator to traverse the list
        Iterator iterator = list.iterator();
        System.out.println("List elements : ");
        while (iterator.hasNext())
            System.out.print(iterator.next() + " ");
        System.out.println();
    }
}


List elements :
A B C D E


// Java code to illustrate the use of ListIterator
import java.io.*;
import java.util.*;
class Test {
    public static void main(String[] args)
    {
        ArrayList<String> list = new ArrayList<String>();
        list.add("A");
        list.add("B");
        list.add("C");
        list.add("D");
        list.add("E");
        // ListIterator to traverse the list
        ListIterator iterator = list.listIterator();
        // Traversing the list in forward direction
        System.out.println("Displaying list elements in forward direction : ");
        while (iterator.hasNext())
            System.out.print(iterator.next() + " ");
        System.out.println();
        // Traversing the list in backward direction
        System.out.println("Displaying list elements in backward direction : ");
        while (iterator.hasPrevious())
            System.out.print(iterator.previous() + " ");
        System.out.println();
    }
}


Displaying list elements in forward direction :
A B C D E
Displaying list elements in backward direction :
E D C B A