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android - How to write an ArrayList to file and retrieve it?

now im trying to use this

FileOutputStream fos = getContext().openFileOutput("CalEvents", Context.MODE_PRIVATE);
    ObjectOutputStream oos = new ObjectOutputStream(fos);
    oos.writeObject(returnlist);
    oos.close();

in order to save "returnlist" which is an ArrayList to the file "CalEvents" now my question is , is that the right way to do it? and how do i retrieve the list back?

thanks in advance

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by (71.8m points)

Is this what you want to do ?

FileInputStream fis;
try {
    fis = openFileInput("CalEvents");
    ObjectInputStream ois = new ObjectInputStream(fis);
    ArrayList<Object> returnlist = (ArrayList<Object>) ois.readObject();
    ois.close();
} catch (FileNotFoundException e) {
    e.printStackTrace();
} catch (IOException e) {
    e.printStackTrace();
} catch (ClassNotFoundException e) {
    e.printStackTrace();
}

EDIT: Can be simplified:

FileInputStream fis;
try {
    fis = openFileInput("CalEvents");
    ObjectInputStream ois = new ObjectInputStream(fis);
    ArrayList<Object> returnlist = (ArrayList<Object>) ois.readObject();
    ois.close();
} catch (Exception e) {
    e.printStackTrace();
}

Assuming that you are in a class which extends Context (like Activity). If not, then you will have to call the openFileInput() method on an object which extends Context.


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