Question

我正在尝试执行一个程序，它可以读取我放入文件的所有对象。输入效果很好，我放了8个对象，但是当我尝试从文件中读取它们时，它显示了java.io.StreamCorruptedException，它似乎无法显示我输入的所有方法。我不知道自己哪里做错了。有没有其他方法可以实现显示系统中每个对象的功能。谢谢我搜索解决方案 Appending to an ObjectOutputStream 但我无法理解答案，如果有人能解释，我将非常感激

import java.util.*;
import java.io.*;
public class driver
{
    public static void main(String[] args) 
    {
        Scanner keyboard = new Scanner(System.in);
        ObjectOutputStream objOut = null;
        ObjectInputStream objIn = null;
        Pet p = null;
        Person owner = null;

        do{
            System.out.println("what u want to do");
            System.out.println("1.add the pet\n2read the pet\n3get the weight\n4 system exit");
            int option = keyboard.nextInt();
            keyboard.nextLine();

            switch(option)
            {
            case 1:
                try 
                {
                    objOut = new ObjectOutputStream(new FileOutputStream("pet.dat",true));
                    owner = new Person();
                    owner.getInput();
                    System.out.println("Type of pet?(1-Mammal;2-Fish;3-Amphibian");
                    int type = keyboard.nextInt();
                    keyboard.nextLine();
                    switch (type)
                    {
                    case 1:
                        p = new Mammal();
                        p.owner = owner;
                        p.getInput();
                        objOut.writeObject(p);
                        objOut.close();
                        break;
                    case 2:
                        p = new Fish();
                        p.owner = owner;
                        p.getInput();
                        objOut.writeObject(p);
                        objOut.close();
                        break;
                    case 3:
                        p = new Amphibian();
                        p.owner = owner;
                        p.getInput();
                        objOut.writeObject(p);
                        objOut.close();
                        break;
                    }
                } 

                catch (Exception e) 
                {
                    e.printStackTrace();
                    System.out.println("here");
                }

                break;

            case 2:
                try 
                {
                    objIn = new ObjectInputStream(new FileInputStream("pet.dat"));

                    try 
                    {
                        while(true)
                        {
                            p = (Pet)objIn.readObject();
                            System.out.println(p);
                        }

                    } 
                    catch (EOFException e) 
                    {
                        System.out.println("System ends");
                    }
                } 

                catch (Exception e)
                {
                    e.printStackTrace();

                    System.out.println("something in driver");
                }

                break;

            case 3:
                try 
                {
                    objIn = new ObjectInputStream(new FileInputStream("pet.dat"));

                    try 
                    {
                        while(true)
                        {
                            p = (Pet)objIn.readObject();
                            System.out.println(p.getname() + "'s weight is: " + p.getweight());
                        }

                    } 
                    catch (EOFException e) 
                    {
                        System.out.println("System ends");
                    }
                } 

                catch (Exception e)
                {
                    e.printStackTrace();
                    System.out.println("something in driver");
                }
                break;

            case 4:

                System.exit(0);
            }
        }while(true);
    }
}

Answer 1

objOut = new ObjectOutputStream(new FileOutputStream("pet.dat",true));

您无法附加到对象流文件，至少在没有特殊措施的情况下。你得到了StreamCorruptedException：无效的类型代码AC＆＃39;，这确实是一个例外和错误，与你在评论中表达的明显信念相反。关于该主题的数百个问题重复。有关完整说明，请参阅here。

写完所有文件后如何读取文件中的所有对象

1 个答案: