使用ObjectOutputStream自动覆盖对象

Question

When i save a second object, and the first one is deleted from the file, how can i solve this?

public void guardar(){ 
    try {
        ObjectOutputStream oos = new ObjectOutputStream(new 
        FileOutputStream("Datos.obj"));
        Object O[] = new Object[5];
        O[0] = getRfc();
        O[1] = getNombre();
        O[2] = getEdad();
        O[3] = getPuesto();
        O[4] = getSalario();
        oos.writeObject(O);
        oos.flush();
        oos.close();
    } catch (FileNotFoundException ex) {
        Logger.getLogger(datos.class.getName()).log(Level.SEVERE, null, ex);
    } catch (IOException ex) {
        Logger.getLogger(datos.class.getName()).log(Level.SEVERE, null, ex);
    }   
}

Thanks in advance if someone can help me.

Answer 1

You will need to read the file with the first object array. Then create a java.util.ArrayList of object arrays and save first the first object array into it, then the second object into it and then serialize the list containing these two object arrays.

If you have a third object to serialize you have to again read the java.util.ArrayList from the file and append to it the third object and so on.

Just a note: it is better to initially save the first object array into a java.util.ArrayList even though you have only one single object array.