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android storing an arraylist of serialized objects in a file

开发者 https://www.devze.com 2023-04-12 07:20 出处:网络
I want to store an arraylist of objects in a file in order to reach them after the app is opened again.

I want to store an arraylist of objects in a file in order to reach them after the app is opened again.

public class SmsMessage implements Serializable {

    public 开发者_开发知识库static enum MessageType {
        Sent,
        Received;
    };

    private String body;
    private Date date;
    private MessageType type;

    public SmsMessage(String _body, Date _date, MessageType _type) {
        body = _body;
        date = _date;
        type = _type;

    }

}

That's the whole class. I'm saving it like this:

FileOutputStream fout = null;
ObjectOutputStream out = null;
    try {
        fout = context.getApplicationContext()
                    .openFileOutput(FILENAME, Context.MODE_PRIVATE);
        out = new ObjectOutputStream(fout);
        out.writeObject(list);
        out.close();

    } catch (IOException ioe) {
        System.out.println("Error in save method");

    } finally {
        out.close();
        fout.close();
}

and read it like this:

ObjectInputStream in = null;
FileInputStream fis = null;
    try {
        fis = context.getApplicationContext().openFileInput(FILENAME);
        in = new ObjectInputStream(fis);
        ArrayList<SmsMessage> list = null;
        list = (ArrayList<SmsMessage>)in.readObject();
    } catch (Exception ex) {
        System.out.println("Error in get method");
    } finally {
        in.close();
        fis.close();
}

This code doesn't work - I mean when I'm saving a full arraylist and kill the app, it returns nothing when I'm trying to read it again when the application is opened. What's wrong here?


Initialise like this:

    fout=new FileOutputStream(FILENAME));

after out.writeObject(list); add this line

     out.flush();   

similarlly initialise

      fis = new FileInputStream((FILENAME));

Hope this works....r u getting any error message on logcat??

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