android在文件中存储序列化对象的arraylist

时间:2011-10-11 04:17:14

标签: android file serialization

我想在文件中存储对象的arraylist,以便在再次打开应用后与他们联系。

public class SmsMessage implements Serializable {

    public 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;

    }

}

那是整个班级。我是这样保存的:

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();
}

并按如下方式阅读:

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();
}

这段代码不起作用 - 我的意思是当我保存完整的arraylist并杀死应用程序时,当我在打开应用程序时再次尝试读取它时,它什么都不会返回。这有什么不对?

1 个答案:

答案 0 :(得分:0)

初始化如下:

    fout=new FileOutputStream(FILENAME));
在out.writeObject(list)之后

;添加此行

     out.flush();   

类似初始化

      fis = new FileInputStream((FILENAME));

希望这有效....你在logcat上收到任何错误信息吗?