concreteaggregate.java

来自「《Java与模式》一书的源代码」· Java 代码 · 共 43 行

package com.javapatterns.iterator.blackbox;

public class ConcreteAggregate extends Aggregate
{
    private Object[] objs = {"Monk Tang",
        "Monkey", "Pigsy",
        "Sandy", "Horse"};

    public Iterator createIterator()
    {
        return new ConcreteIterator();
    }

    private class ConcreteIterator
    implements Iterator
    {
        private int currentIndex = 0;

        public void first()
        {
            currentIndex = 0;
        }

        public void next()
        {
            if (currentIndex < objs.length)
            {
                currentIndex++;
            }
        }

        public boolean isDone()
        {
            return (currentIndex == objs.length);
        }

        public Object currentItem()
        {
            return objs[currentIndex];
        }
    }
}