iterator

定义 ；Provide a way to access the elements of an aggreate object sequentially without exposing its underlying representation

提供一种方法访问一个容器对象中的各种元素，而又不需要暴露对该对象的内部可见性

 

类图

 

 

package Iterator;

import java.util.ArrayList;

public interface Aggregate  extends Iterable{
 ArrayList list =new ArrayList();

}

 

package Iterator;

import java.util.Iterator;

public class ConcreteAggregate implements Aggregate{
 
     Iterator iterator=new ConcreteIterator();
 
 public Iterator iterator() {
  
  return iterator;
 }
 

}

package Iterator;

import java.util.ArrayList;
import java.util.Iterator;

public class ConcreteIterator implements Iterator{
 ArrayList list=new ArrayList();  

 @Override
 public boolean hasNext() {
  // TODO Auto-generated method stub
  return false;
 }

 @Override
 public Object next() {
  // TODO Auto-generated method stub
  return null;
 }

 @Override
 public void remove() {
  // TODO Auto-generated method stub
  
 }

}