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标题: ObjectInputStream类读取 [打印本页]

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作者: 李靖    时间: 2012-10-29 12:46
标题: ObjectInputStream类读取


如果通过ObjectOutputStream往磁盘文件写入若干个对象，如何通过ObjectInputStream读到所有的对象呢，通过while循环
public static void main(String[] args) throws Exception {
  Person person=new Person("wangwu",13);
  Person person1=new Person("zhangsan",13);
  ObjectOutputStream objectOutputStream=new ObjectOutputStream(new FileOutputStream("demo.txt"));
  objectOutputStream.writeObject(person);
  objectOutputStream.writeObject(person1);
  objectOutputStream.flush();
  objectOutputStream.close();
  ObjectInputStream objectInputStream=new ObjectInputStream(new FileInputStream("demo.txt"));
  Object object;
  while((object=objectInputStream.readObject()) !=null){
   System.out.println(((Person)object).getName());
  }
}
下面代码会报
Exception in thread "main" java.io.EOFException
at java.io.ObjectInputStream$BlockDataInputStream.peekByte(Unknown Source)
at java.io.ObjectInputStream.readObject0(Unknown Source)
at java.io.ObjectInputStream.readObject(Unknown Source)
at com.io.lijing.ObjectStream.main(ObjectStream.java:22)

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作者: 张忠豹    时间: 2012-10-29 13:18

1. package java1.io;
   
2. 
   
3. import java.io.FileInputStream;
   
4. import java.io.FileOutputStream;
   
5. import java.io.ObjectInputStream;
   
6. import java.io.ObjectOutputStream;
   
7. import java.io.Serializable;
   
8. 
   
9. public class ObjectStreamTest {
   
10. 
    
11. /**
    
12. * @param args
    
13. */
    
14. public static void main(String[] args) throws Exception {
    
15. Person person=new Person("wangwu",13);
    
16. Person person1=new Person("zhangsan",13);
    
17. ObjectOutputStream objectOutputStream=new ObjectOutputStream(new FileOutputStream("demo.txt"));
    
18. objectOutputStream.writeObject(person);
    
19. objectOutputStream.writeObject(person1);
    
20. //应该写入循环结束标记
    
21. objectOutputStream.writeObject(null);
    
22. objectOutputStream.flush();
    
23. objectOutputStream.close();
    
24. ObjectInputStream objectInputStream=new ObjectInputStream(new FileInputStream("demo.txt"));
    
25. Object object =null;
    
26. while((object=objectInputStream.readObject()) !=null){
    
27. System.out.println(object);
    
28. System.out.println(((Person)object).getName());
    
29. }
    
30. }
    
31. 
    
32. 
    
33. }
    
34. class Person implements Serializable{
    
35. private String name;
    
36. private int age;
    
37. 
    
38. public Person(String name,int age){
    
39. this.name = name;
    
40. this.age = age;
    
41. }
    
42. 
    
43. public String getName() {
    
44. return name;
    
45. }
    
46. }
    

复制代码

应该写入循环结束标记！

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