步骤 :装箱(1)先将数据装箱实体对象.
(2)多个实体对象在装箱给实体.
(3)实体集合在保存到文件
拆箱:(1)先将文件中的数据拆给集合
(2)集合拆给对象
(3)集合拆给实体
public class FIle_01 {
public static void main (String [] args) throws IOException, IOException{
//数据存入集合
ArrayList <Apple> list = new ArrayList<Apple>();
list.add(new Apple("001",12,30));
list.add(new Apple("002",22,40));
//集合保存到文件
ObjectOutputStream ob = new ObjectOutputStream( new FileOutputStream("D://22.txt"));
ob.writeObject(list);
//文件写入集合
ObjectInputStream ib = new ObjectInputStream(new FileInputStream("D://22.txt"));
try {
List <Apple>obj = (List<Apple>) ib.readObject() ;
System.out.println(obj);
// 集合写入对象
for(Apple app:obj){
System.out.println(app);
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
}