设计模式之迭代器模式（Iterator）

package Iterator;
/**
 *抽象迭代器
 * 2014-8-14下午2:07:14-limiracle
 */
public interface Iterator {
    //遍历到下一个元素
    public Object next();
    //是否已经遍历到尾部
    public boolean hasNext();
    //删除当前指定的元素
    public boolean remove();
}

package Iterator;

import java.util.Vector;
/**
 *具体迭代器
 * 2014-8-14下午2:16:02-limiracle
 */
public class ConcreteIterator implements Iterator{
    private Vector vector = new Vector();
    //定义当前游标
    public int cursor=0;
    public ConcreteIterator(Vector vector){
        this.vector=vector;
    }
    public Object next() {
        Object result=null;
        if(this.hasNext()){
            result=this.vector.get(this.cursor++);
        }else{
            result =null;
        }
        return result;
    }
    //判断是否到达尾部
    public boolean hasNext() {
        if(this.cursor==this.vector.size()){
            return false;
        }else{
            return true;
        }
    }
    //删除当前元素
    public boolean remove() {
        this.vector.remove(this.cursor);
        return true;
    }
    
}

package Iterator;
/**
 *抽象容器
 * 2014-8-14下午3:04:29-limiracle
 */
public interface Aggregate {
    //是容器必然有元素的增加
    public void add(Object object);
    //减少元素
    public void remove(Object object);
    //由迭代器来遍历所有的元素
    public Iterator iterator();
}

package Iterator;

import java.util.Vector;
/**
 *具体容器
 * 2014-8-14下午3:07:30-limiracle
 */
public class ConcreteAggregate implements Aggregate{
    //容纳对象的容器
    private Vector vector=new Vector();
    //增加一个元素
    public void add(Object object){
        this.vector.add(object);
    }
    //返回迭代器对象
    public Iterator iterator(){
        return new ConcreteIterator(this.vector);
    }
    //删除一个元素
    public void remove(Object object){
        this.remove(object);
    }
}