Serializable bliver min skæbne

Ja, nu har jeg så kæmpet med at serialize en klasse i alt for lang tid. Det er ingen problemer med at skrive objektet, men jeg får en IOException når jeg vil læse objektet igen! Hvad gør jeg galt?
public void loadUserDataBase() {
try {

myUserDataBase = getUserDataBase();

}   
} catch (IOException e) {
System.out.println("IOException");
} catch (ClassNotFoundException e) {
System.out.println("no file on harddisk");
}
       
}

    public void saveUserDataBase() {
           
        try {
               
        putUserDataBase(myUserDataBase);
    System.out.println("UserDataBasen er Gemt");
        } catch (IOException e) {
    System.out.println("Could not save userDataBase");
            }
        }
   
}

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import java.io.*;


public class SerializedUserDataBaseFile extends SerializedObjectFile {
   

    public SerializedUserDataBaseFile(String filename) {
        super(filename);
    }
   
   
    public void putUserDataBase(UserDataBase myUserDataBase) throws IOException {
        putObject(myUserDataBase);
    }
   
   
   
    public UserDataBase getUserDataBase() throws IOException, ClassNotFoundException {
       
        getObject();
        if (getObject() == null) {
            return null;
        }
        return (UserDataBase) getObject();
    }
    }
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import java.io.*;

public class SerializedObjectFile {

    final protected String filename;

    public SerializedObjectFile(String filename) {
        this.filename = filename;
    }
   
protected void putObject(Serializable myUserDataBase) throws IOException {
               
    FileOutputStream outStream;
    ObjectOutputStream objStream;
    outStream = new FileOutputStream(filename);
    objStream = new ObjectOutputStream(outStream);
    objStream.writeObject(myUserDataBase);
    objStream.flush();
    objStream.close();
    }
   

protected Object getObject() throws IOException, ClassNotFoundException {
        try {
           
    Object myObject;
    FileInputStream inStream;
    ObjectInputStream objStream;
    inStream = new FileInputStream(filename);
    objStream = new ObjectInputStream(inStream);
    myObject = (UserDataBase) objStream.readObject();
    objStream.close();
    return (UserDataBase) myObject;
        }
        catch (FileNotFoundException e) {
        System.out.println("!no such file!");
            return null;
           
        }
    }
}
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