2016-12-25 59 views
0

我有序列化对象并将其存储在二进制文件中的功能,也是另一个对象,用于统计目前为止我已存储在文件中的对象数量,因此我可以使用计数器稍后再通过该文件并反序列化并阅读它。 这是我写的功能:从java中的二进制文件中读取对象

Class2 dad = new Class2(DadName.getText(), DadLastName.getText()); 

Class1 son = new Class1(FirstName.getText(), dad, "Session"); 

// Write object to file 
FileOutputStream outStream = new FileOutputStream(new File("MainStore.dat"), true); 
ObjectOutputStream objectOutputFile = new ObjectOutputStream(outStream); 
objectOutputFile.writeObject(son); 
objectOutputFile.close(); 


// Update the objectcounter file by 
// Maintenance is a class I use just to save object contain information about number of files,increase them, decrease them. 

Maintenance check = new Maintenance(); 
FileInputStream inStream = new FileInputStream("Counter.dat"); 
ObjectInputStream objectInput = new ObjectInputStream(inStream); 
check = (Maintenance) objectInput.readObject(); 
inStream.close(); 

check.increaseObject(); 

FileOutputStream outStream1 = new FileOutputStream("Counter.dat"); 
ObjectOutputStream objectOutputFile1 = new ObjectOutputStream(outStream1); 

objectOutputFile1.writeObject(check); 
objectOutputFile1.close(); 

先前的功能工作得很好,下一步就是函数读取读取的对象从文件回来,我用Counter.dat看到存储在MainStore对象的数量。 dat,它给了我正确的编号。 这里是读功能:

// Read Counter file to know how many stored objects to go through them 
Maintenance check = new Maintenance(); 
FileInputStream inStream = new FileInputStream("Counter.dat"); 
ObjectInputStream objectInput = new ObjectInputStream(inStream); 
check = (Maintenance) objectInput.readObject(); 
int Counter1 = check.getObjectsNumber(); // function I created in the Maintenance class to return number of object stored 
inStream.close(); 


// Read the stored objects 
//here is my problem begin 

FileInputStream inStream2 = new FileInputStream("MainStore.dat"); 
ObjectInputStream objectInputFile = new ObjectInputStream(inStream2); 

// Create array of objects 
Class1[] arrayOfObjects = new Class1[Counter1]; 

// Read the serialized objects from the file. 
for (int i = 0; i < Counter1; i++) { 
arrayOfObjects[i] = (Class1) objectInputFile.readObject(); // here is the error pointed by compiler 
} 
objectInputFile.close(); 

for (int i = 0; i < 2; i++) { 
// here I should have array of all objects ready to read details 

} 

一切都看起来不错,除了最后一位“//读取从序列化对象”。它给了我这个错误

Caused by: java.io.StreamCorruptedException: invalid type code: AC 
    at java.io.ObjectInputStream.readObject0(Unknown Source) 
    at java.io.ObjectInputStream.readObject(Unknown Source) 
    at registerController.CheckPlaceAvailabilityAction(registerController.java:120) 
    ... 58 more 

,当我只有读一个对象来测试它,它的工作完美,并返回第一个存储的对象对我来说,错误发生了,当我尝试读取所有存储的对象。

+0

如果可以,您可能需要发布MVCE(http://stackoverflow.com/help/mcve)。 –

+0

你为什么要坚持柜台?你确定你的文件在测试过程中没有被损坏吗?我建议删除它并重新开始一个新文件。 – JimmyB

回答

1

显然,你不能像你一样透明地连接/追加ObjectOutputStreams

参见the docs

[该]构造序列化流报头写入 底层流

因此,一个新的数据流将首先写一些头,这将需要一个新的输入流读书。否则,输入流会尝试将标题作为序列化对象读取,并会失败,因为这些标题不是有效的序列化对象数据。