一对多映射

class  一对多映射
{
	public static void main(String[] args) 
	{
		//第一步：根据结构设置获取数据
		Item item = new Item(1L,"图书分类");
		Subitem[] subitems = new Subitem[]{
			new Subitem(10L,"小说"),
			new Subitem(11L,"名著")
		};

	for(int x = 0;x <subitems.length;x++ ){
		subitems[x].setItem(item);
	}
	item.setSubitems(subitems);
		//第二步：根据要求获取数据
	for (int x = 0;x < item.getSubitem().length ;x++ )
	{
		System.out.println("-\t"+item.getSubitem()[x].getInfo());
	}
		
		
	}
}

class Item
{
	private long iid;		//分类ID
	private String title;	//名称
	private Subitem[] Subitems;//一个分类下面有多个子分类

	public Item(long iid,String title){ //构造方法
		this.iid = iid;
		this.title = title;
	}

	public void  setSubitems(Subitem[] Subitems){	//得到Subitems数据
		this.Subitems = Subitems;
	}
	
	public Subitem[] getSubitem(){					//返回Subitem数据
		return this.Subitems;	
	}

	public String getInfo(){
		return "【分类信息】"+"iid="+this.iid+"title"+this.title;
	}
}

class Subitem
{
	private long sid;		//分类ID
	private String title;	//名称
	private Item Item;		//一个上级分类

	public Subitem(long sid,String title){	//构造方法
		this.sid = sid;
		this.title = title;
	}

	public void  setItem(Item Item){	//得到Subitems数据
		this.Item = Item;
	}
	
	public Item getItem(){					//返回Subitem数据
		return this.Item ;	
	}

	public String getInfo(){
		return "【子分类信息】"+"sid="+this.sid+"title="+this.title;
	}
} 

标签：Subitems,String,映射,title,Item,Subitem,一对,public
来源： https://blog.csdn.net/weixin_46245201/article/details/110006340