1.迭代模式 //例如实现iterator接口的模型可以用foreach方法
2.实例
public interface Iterator { public Boolean hashNext(); public Integer next(); } public class IteratorImp { private ArrayList<Integer> list; public IteratorImp(ArrayList<Integer> list) { super(); this.list = list; } public MyIterator iterator() { return new MyIterator(); } class MyIterator implements Iterator { private int size = list.size(); private int i = 0; @Override public Boolean hashNext() { if (i < size) { return true; } return false; } @Override public Integer next() { if (i < size) { i++; } return list.get(i - 1); } } }