Writing object to file

Question

I have a method that's supposed to write an object to a file. I've tried a variety of methods but I either don't write to the file or I go into my catch statement, my code is as follows:

public void createFoo(Foo foo)
{
    ObjectOutputStream out = null;
    try
    {
        out = new ObjectOutputStream(new FileOutputStream("C:\\Users\\PERSON\\AndroidStudioProjects\\PROJECT\\bar.dat"));
        out.writeObject(event);
        Log.i("CreateFoo", "Write success");
    }
    catch (IOException e)
    {
        Log.i("CreateFoo", "Write - Catch error can't find .dat");
    }
    finally
    {
        try
        {
            out.close();
        }
        catch (Exception e)
        {
            Log.i("CreateFoo", "Write - Failed to close object output stream.");
        }
    }
}

I've tried looking at other threads but I'm still having trouble, my Foo object also has implements Serializable in its declaration.

score 0 · Answer 1 · answered Mar 13 '15 at 00:38

0

Your Android device does not have a C:\\Users\\PERSON\\AndroidStudioProjects\\PROJECT\\ directory, largely because Android is not Windows, so Android does not have drive letters. Also, you cannot write to just any directory in Android -- your app is limited to internal storage, external storage, and (on Android 4.4+) removable storage.

Also, in the future, when you ask questions on Stack Overflow about how your app is crashing, use LogCat and post the stack trace.

answered Mar 13 '15 at 00:38

CommonsWare

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I'm using the Android Studio emulator so I thought it would look in its file directory for the .dat. Will storing to external storage store in a Windows directory? – Dan Mar 13 '15 at 00:52
@Dan External storage for the emulator is a disk image. Files your app on the emulator writes to external storage will be inside that disk image file. – CommonsWare Mar 13 '15 at 01:02

score 0 · Answer 2 · answered Mar 13 '15 at 01:41

Replacing

out = new ObjectOutputStream(new FileOutputStream("C:\\Users\\PERSON\\AndroidStudioProjects\\PROJECT\\bar.dat"));

with

File outFile = new File(Environment.getExternalStorageDirectory(), "bar.data");
        out = new ObjectOutputStream(new FileOutputStream(outFile));

Did the trick, thanks for the help!

Writing object to file

2 Answers2