练习：序列化集合

Posted 2020-12-20 yhqtv-com

 1 package com.itheima.demo04.ObjectStream;
 2 
 3 import java.io.*;
 4 import java.util.ArrayList;
 5 
 6 /*
 7     练习：序列化集合
 8         当我们想在文件中保存多个对象的时候
 9         可以把多个对象存储到一个集合中
10         对集合进序列化和反序列化
11     分析:
12         1.定义一个存储Person对象的ArrayList集合
13         2.往ArrayList集合中存储Person对象
14         3.创建一个序列化流ObjectOutputStream对象
15         4.使用ObjectOutputStream对象中的方法writeObject,对集合进行序列化
16         5.创建一个反序列化ObjectInputStream对象
17         6.使用ObjectInputStream对象中的方法readObject读取文件中保存的集合
18         7.把Object类型的集合转换为ArrayList类型
19         8.遍历ArrayList集合
20         9.释放资源
21  */
22 public class Demo03Test {
23     public static void main(String[] args) throws IOException, ClassNotFoundException {
24         //1.定义一个存储Person对象的ArrayList集合
25         ArrayList<Person> list = new ArrayList<>();
26         //2.往ArrayList集合中存储Person对象
27         list.add(new Person("张三",18));
28         list.add(new Person("李四",19));
29         list.add(new Person("王五",20));
30         //3.创建一个序列化流ObjectOutputStream对象
31         ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("10_IO\list.txt"));
32         //4.使用ObjectOutputStream对象中的方法writeObject,对集合进行序列化
33         oos.writeObject(list);
34         //5.创建一个反序列化ObjectInputStream对象
35         ObjectInputStream ois = new ObjectInputStream(new FileInputStream("10_IO\list.txt"));
36         //6.使用ObjectInputStream对象中的方法readObject读取文件中保存的集合
37         Object o = ois.readObject();
38         //7.把Object类型的集合转换为ArrayList类型
39         ArrayList<Person> list2 = (ArrayList<Person>)o;
40         //8.遍历ArrayList集合
41         for (Person p : list2) {
42             System.out.println(p);
43         }
44         //9.释放资源
45         ois.close();
46         oos.close();
47     }
48 }

 1 package com.yhqtv.demo06.trycatch;
 2 
 3 import java.io.*;
 4 import java.util.ArrayList;
 5 
 6 /*
 7  * @author  XMKJ  yhqtv.com Email:[e-mail]
 8  * @create 2020-05-13-18:41
 9  *
10  */
11 public class Test01 {
12     public static void main(String[] args) throws IOException, ClassNotFoundException {
13         ArrayList<Student>  list=new ArrayList<>();
14 
15         list.add(new Student("tom",18));
16         list.add(new Student("jack",13));
17         list.add(new Student("lucy",22));
18         list.add(new Student("lily",15));
19 
20         ObjectOutputStream oos=new ObjectOutputStream(new FileOutputStream("C:\list.txt"));
21         oos.writeObject(list);
22 
23         ObjectInputStream ois=new ObjectInputStream(new FileInputStream("C:\list.txt"));
24         Object o = ois.readObject();
25         ArrayList o1 = (ArrayList) o;
26 
27         for (Object o2 : o1) {
28             System.out.println(o2);
29         }
30 
31         oos.close();
32         ois.close();
33 
34     }
35 }

 1 package com.yhqtv.demo06.trycatch;
 2 
 3 import jdk.internal.org.objectweb.asm.commons.SerialVersionUIDAdder;
 4 
 5 import java.io.Serializable;
 6 
 7 /*
 8  * @author  XMKJ  yhqtv.com Email:[e-mail]
 9  * @create 2020-05-13-18:44
10  *
11  */
12 public class Student implements Serializable {
13     private static final  long serialVersionUID=23432L;
14     private String name;
15     private int age;
16 
17     public Student() {
18     }
19 
20     public Student(String name, int age) {
21         this.name = name;
22         this.age = age;
23     }
24 
25     public String getName() {
26         return name;
27     }
28 
29     public void setName(String name) {
30         this.name = name;
31     }
32 
33     public int getAge() {
34         return age;
35     }
36 
37     public void setAge(int age) {
38         this.age = age;
39     }
40 
41     @Override
42     public String toString() {
43         return "Student{" +
44                 "name=‘" + name + ‘‘‘ +
45                 ", age=" + age +
46                 ‘}‘;
47     }
48 }