Java——对象数组和对象流

 1 import java.io.File;
 2 import java.io.FileInputStream;
 3 import java.io.FileNotFoundException;
 4 import java.io.FileOutputStream;
 5 import java.io.IOException;
 6 import java.io.InputStream;
 7 import java.io.ObjectInputStream;
 8 import java.io.ObjectOutputStream;
 9 import java.io.OutputStream;
10 import java.io.Serializable;
11 import java.util.Arrays;
12 
13 class Student implements Serializable
14 {
15     /**
16      * 序列化的类
17      */
18     private static final long serialVersionUID = 1L;
19     public String name;
20     public int age;
21     public String IdCard;
22     public Student(String name, int age, String idCard) {
23         super();
24         this.name = name;
25         this.age = age;
26         IdCard = idCard;
27     }
28     public String getName() {
29         return name;
30     }
31     public void setName(String name) {
32         this.name = name;
33     }
34     public int getAge() {
35         return age;
36     }
37     public void setAge(int age) {
38         this.age = age;
39     }
40     public String getIdCard() {
41         return IdCard;
42     }
43     public void setIdCard(String idCard) {
44         IdCard = idCard;
45     }
46     @Override
47     public String toString() {
48         return "Student [name=" + name + ", age=" + age + ", IdCard=" + IdCard + "]";
49     }
50     public Student() {}
51 }
52 
53 
54 public class OneTime {
         //写对象
55     private static void writeObject()
56       {   //序列化的类，实例化对象数组
57           Student[] st = {new Student("wei",19,"1803050208"),
58                   new Student("zhong",20,"1803050209"),
59                   new Student("wang",21,"1803050211"),
60                   new Student("li",18,"1803050210")};
61           File f = new File("C:\Users\Easyboyxxx\st.obj");
               //对象流
62           try {
63             OutputStream out = new FileOutputStream(f);
64             ObjectOutputStream ob = new ObjectOutputStream(out);
65             ob.writeObject(st);
66             ob.close();
67         } catch (FileNotFoundException e) {
68             e.printStackTrace();
69         } catch (IOException e) {
70             e.printStackTrace();
71         }
72       }
73     private static void readObject()
74     {
75         File f = new File("C:\Users\Easyboyxxx\st.obj");
76         try {
77             InputStream in = new FileInputStream(f);
78             ObjectInputStream ob = new ObjectInputStream(in);
79             Student[] st = (Student[])ob.readObject();  //注意读出的是对象数组，不是单个对象
80             ob.close();
81             System.out.println(Arrays.toString(st));
82         } catch (FileNotFoundException e) {
83             e.printStackTrace();
84         } catch (IOException e) {
85             e.printStackTrace();
86         } catch (ClassNotFoundException e) {
87             e.printStackTrace();
88         }
89         
90     }

   //主方法调用读写方法。
91   public static void main(String args[])
92   {
93       writeObject();
94       readObject();
95       
96   }
97   
98 }