对象序列化的应用，一个文件中存储多个对象

import java.io.Serializable;public class Xuliehualianxi01 implements Serializable {private int id;private String name;private int count;private Double price;public Xuliehualianxi01(int id, String name, int count, Double price) {super();this.id = id;this.name = name;this.count = count;this.price = price;}public int getId() {return id;}public void setId(int id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getCount() {return count;}public void setCount(int count) {this.count = count;}public Double getPrice() {return price;}public void setPrice(Double price) {this.price = price;}}

import java.io.*;import java.util.ArrayList;import java.util.List;public class Xulianxi01 {public static void serial(List<Xuliehualianxi01> list) {ObjectOutputStream oos = null;String dox = "F:/IOtest/xuliehua/save.txt";try {oos = new ObjectOutputStream(new FileOutputStream(dox));oos.writeObject(list);System.out.println("录入新订单成功！");} catch (FileNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();} finally {try {if (oos != null) {oos.flush();oos.close();}} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}public static List<Xuliehualianxi01> unserial() {ObjectInputStream ois = null;List<Xuliehualianxi01>  list = new ArrayList<>();Xuliehualianxi01 x = null;String dox = "F:/IOtest/xuliehua/save.txt";try {ois = new ObjectInputStream(new FileInputStream(dox));//list=(ArrayList<Xuliehualianxi01>) ois.readObject();// 用下面方式，追加对象序列，用上面的方式，是覆盖，相当于一个新的对象。list.addAll((ArrayList<Xuliehualianxi01>)ois.readObject());} catch (FileNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();} finally {try {if (ois != null) {ois.close();}} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}return list;}public static void main(String[] args) {File f = null;List<Xuliehualianxi01> list1 = new ArrayList<>();List<Xuliehualianxi01> list2 = new ArrayList<>();double money = 0.0;list2.add(new Xuliehualianxi01(1, "卫生纸", 10, 45.0));list2.add(new Xuliehualianxi01(2, "水杯", 2, 34.0));list2.add(new Xuliehualianxi01(3, "电脑", 1, 4565.0));list2.add(new Xuliehualianxi01(4, "键盘", 10, 792.0));list2.add(new Xuliehualianxi01(5, "手机", 3, 6288.0));f = new File("F:/IOtest/xuliehua/save.txt");if (f.exists()) {list1 = unserial();for (int i = 0; i < list1.size(); i++) {System.out.println("用户买了" +  list1.get(i).getCount() + "个" + list1.get(i).getName() + ",价格为" + list1.get(i).getCount() * list1.get(i).getPrice() + "元");money += list1.get(i).getCount() * list1.get(i).getPrice();}System.out.println("用户总共需要付款：" + money + "元");} else {serial(list2);}}}