Java Collection - 如何fetch带有迭代器的元素

Using an iterator from a List is like using any other iterator. 
The order of the elements in the list is preserved.


import java.util.Arrays;
import java.util.Iterator;
import java.util.List;

public class MainClass {
  public static void main(String[] a) {

    List list = Arrays.asList(new String[] { "A", "B", "C", "D" });
    Iterator iter = list.iterator();

    while (iter.hasNext()) {
      System.out.println(iter.next());
    }

  }
}

运行结果如下:

Looping through a Collection object: while loop, iterator, and for each

import java.util.ArrayList;
import java.util.Iterator;
//  w  w  w. j av  a  2s.c o  m
public class Main {
  public static void main(String[] args) {
    ArrayList<String> list = new ArrayList<String>();

    list.add("Monday");
    list.add("Tuesdag");
    list.add("Wednesday");
    list.add("Thursday");
    list.add("Friday");
    list.add("Saturday");
    list.add("Sunday");

    Iterator<String> iterator = null;

    iterator = list.iterator();
    while (iterator.hasNext()) {
      String element = iterator.next();
      System.out.println(element);
    }

    for (iterator = list.iterator(); iterator.hasNext();) {
      String element = iterator.next();
      System.out.println(element);
    }

    for (String element : list) {
      System.out.println(element);
    }
  }
}

运行结果如下: