课时38：综合实战：一对多映射

Class Item {
private long iid ;
private string title ;
private Subitem subitems[];
public Item(long iid,String title) {
this.iid = iid ;
this.title = title;
}
public void setSubitems (Subitem subitems [] ) {
this .subitems = subitems ;
}
public Subitem[]getSubitems() {
return this.subitems ;
}
public string getInfo() {
return "【分类信息】iid = " + this.iid +"、title = " + this.title；
}
}
Class Subitem {
private long sid ;
private String title ; I
private Item item ;
public Subitem(long sid,String title) {
this.sid = sid ;
this.title = title ;
}
public void setItem (Item item){
this.item =item;
}
public Item getItem() {
return this.item ;
}
public string getInfo() {
return "【子分类信息】sid = " + this.sid +"、title = " + this.title；
}
}
public class JavaDemo {
public static void main(String args[]){
// 第一步:根据结构设置对象数据
Item item = new Item(1L,"图书");
Subitem subitems [] = new Subitem []{
New Subitem(10L,"编程图书”)，
New Subitem(10L,"图形图像类图书")
};
item.setSubitems (subitems);//一个分类下有多个子分类
for (int x = 0 ; x< subitems.length ;x++){
subitems [x].setItem(item);
}
// 第二步:根据要求获取数据
System.out.println(item.getInfo());
for (int x =0; x< item.getSubitems().length ; x ++){
System.out.println("\t|-"+ item.getSubitems () [x].getInfo()) ;
}
}
}