深入理解Java设计模式之迭代器模式

public interface IListCollection
{
    Iterator GetIterator();
}

public interface Iterator
{
    bool MoveNext();
    Object GetCurrent();
    void Next();
    void Reset();
}

public class ConcreteList : IListCollection
{
    int[] collection;
    public ConcreteList()
    {
        collection = new int[] { 2, 4, 6, 8 };
    }
    public Iterator GetIterator()
    {
        return new ConcreteIterator(this);
    }
    public int Length
    {
        get { return collection.Length; }
    }
    public int GetElement(int index)
    {
        return collection[index];
    }
}

public class ConcreteIterator : Iterator
{
    // 迭代器要集合对象进行遍历操作，自然就需要引用集合对象
    private ConcreteList _list;
    private int _index;
    public ConcreteIterator(ConcreteList list)
    {
        _list = list;
        _index = 0;
    }
    public bool MoveNext()
    {
        if (_index < _list.Length)
        {
            return true;
        }
        return false;
    }
    public Object GetCurrent()
    {
        return _list.GetElement(_index);
    }
    public void Reset()
    {
        _index = 0;
    }
    public void Next()
    {
        if (_index < _list.Length)
        {
        _    index++;
        }
    }
}

class Program
{
    static void Main(string[] args)
    {
        Iterator iterator;
        IListCollection list = new ConcreteList();
        iterator = list.GetIterator();
        while (iterator.MoveNext())
        {
            int i = (int)iterator.GetCurrent();
            Console.WriteLine(i.ToString());
            iterator.Next();
        }
        Console.Read();
    }
}

public interface IEnumerator
 {
      object Current
      {
           get;
      }
     bool MoveNext();
     void Reset();
 }

public interface IEnumerable
{
    IEumerator GetEnumerator();
}