File object can't find the file when there is one

Question

In my app After user clicks on a button ,the download manager starts to download a file from internet and saving it to the internal sd card using this code:

void startDownload()
    {
        Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).mkdirs();        
        download_req.setAllowedNetworkTypes(DownloadManager.Request.NETWORK_WIFI | DownloadManager.Request.NETWORK_MOBILE)
        .setAllowedOverRoaming(false)
        .setTitle(PersianReshape.reshape("Downloading"))
        .setDescription(PersianReshape.reshape("currently downloading the file..."))
        .setDestinationInExternalPublicDir(Environment.getExternalStorageDirectory().getAbsolutePath() , packageId + ".sqlite");
        download_ID = mgr.enqueue(download_req);
    }

After it is downloaded, I plan to check its existance everytime app runs with this code:

String DatabaseAddress =
Environment.getExternalStorageDirectory().getAbsolutePath() +
"/ee.sqlite";
File file = new File(DatabaseAddress);
Log.d("PATH File: ", DatabaseAddress);
if (file.exists()){
Toast.makeText(getApplicationContext(), "found", Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(getApplicationContext(), "not found", Toast.LENGTH_SHORT).show();
}

Now when I run this code it returns "not found" message whereas the file is already there (I checked its existance using a file manager).

the device I test on is nexus 7 and path used in saving the download file is: /storage/emulated/0/ee.sqlite

ee.sqlite is the filename of downloaded file.

/storage/emulated/0/ is the default path returned by app

Permissions added to manifest for this code are:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

Q: Why does file.exists() returns false when there is a file?

UPDATE: WHEN I USE HARDCODE

File temp = new File("/sdcard/storage/emulated/0/", "ee.sqlite");

it works but when I use Environment.getExternalStorageDirectory().getPath() it doesn't.

Try to print `file.getAbsolutePath()`: they (files) may be in different directories. Another possible reason is permissions, but I don't think it's because of permissions. — 18446744073709551615, Nov 18 '13 at 06:02
file.getAbsolutePath returns the same address as file.getPath(). — Nima Sakhtemani, Nov 18 '13 at 06:04
I mean that the destination path of the download and the path that you check for existence may be different. — 18446744073709551615, Nov 18 '13 at 06:28
BTW, did you mention that in your code you use getExternalStoragePublicDirectory() in one place and getExternalStorageDirectory() in the other? — 18446744073709551615, Nov 18 '13 at 06:41
If they are the same, `Log.d("~~~", "----" + new File(file.getAbsolutePath()).exists())` should print true while `Log.d("~~~", "----" + file.exists())` prints false. This would be absurd, and also would mean a bug. — 18446744073709551615, Nov 18 '13 at 06:44
By the way, sometimes spaces may creep in paths. Please print the path as `Log.d("~~~","path=["+path+"]");` — 18446744073709551615, Nov 18 '13 at 06:46
I used Environment.getExternalStorageDirectory().getAbsolutePath() in both classes of my code. — Nima Sakhtemani, Nov 18 '13 at 06:50
let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/41397/discussion-between-user1290467-and-18446744073709551615) — Nima Sakhtemani, Nov 18 '13 at 08:42

Avijit · Answer 1 · 2013-11-18T07:51:35.090

1

Just initialize the File like this:

Updated: This is just because of the separator missing there:

 public static File getExternalStorageDirectory() {
    return EXTERNAL_STORAGE_DIRECTORY;
}

and EXTERNAL_STORAGE_DIRECTORY is:

private static final File EXTERNAL_STORAGE_DIRECTORY
        = getDirectory("EXTERNAL_STORAGE", "/sdcard");

static File getDirectory(String variableName, String defaultPath) {
    String path = System.getenv(variableName);
    return path == null ? new File(defaultPath) : new File(path);
}

String baseDir = EXTERNAL_STORAGE_DIRECTORY ;
String fileName = "ee.sqlite";

// Not sure if the / is on the path or not
File file = new File(baseDir + File.separator + fileName);
if (file.exists()) {
        Toast.makeText(getApplicationContext(), "found", Toast.LENGTH_SHORT).show(); 
    }
else{
        Toast.makeText(getApplicationContext(), "not found", Toast.LENGTH_SHORT).show();
    }

2nd Possibilites: As you are running it in emulator you have to make sure you have external storage enabled Like this:

In Eclipse, go to Window > Android SDK and AVD Manager. Select the appropriate AVD and then click Edit.

Window - Android SDK and AVD Manager

Make sure you have SD card support enabled. If you do not, click the "New" button and select the "SD Card Support" option.

Edit screen

edited Nov 18 '13 at 07:51

answered Nov 18 '13 at 06:07

Avijit

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How you gave the dirName and fileName? – Avijit Nov 18 '13 at 06:14
yes ,String dirName = Environment.getExternalStorageDirectory().getAbsolutePath(); and String fileName = "ee.sqlite"; – Nima Sakhtemani Nov 18 '13 at 06:17
Tried it but it still doesn't work. only hard coded string works. – Nima Sakhtemani Nov 18 '13 at 06:29
This is just because of the separator. You didn't gave there. I have mentioned it in my updated section and updated my answer – Avijit Nov 18 '13 at 06:33
See my 2nd possibilties section – Avijit Nov 18 '13 at 06:54
I'm testing the app on 2012 Nexus 7 running JB 4.3. – Nima Sakhtemani Nov 18 '13 at 06:55
What is returning by 'Log.d("PATH File: ", DatabaseAddress);' – Avijit Nov 18 '13 at 07:10
Emulator returns: /storage/sdcard/ee.sqlite and nexus 7 returns: /storage/emulated/0/ee.sqlite – Nima Sakhtemani Nov 18 '13 at 07:22
see this http://stackoverflow.com/questions/13737261/nexus-4-not-showing-files-via-mtp – Avijit Nov 18 '13 at 07:44
As you can see in nexus 7 you didnt get any option like /sdcard right? So do onething like call the external storage like my updated answer and let me know it helps you or not? – Avijit Nov 18 '13 at 07:50
I'm sorry but it didn't help. the only way that could make it work is adding the string "/sdcard/". --> File file = new File("/sdcard/" + dirName + File.separator , fileName); Works but yours doesn't. – Nima Sakhtemani Nov 18 '13 at 08:41
let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/41396/discussion-between-user1290467-and-andru) – Nima Sakhtemani Nov 18 '13 at 08:41

score 1 · Answer 2 · answered Nov 18 '13 at 09:47

Finally got it to work by changing the File object.

The solution is to change the File object to the following:

File file = new File(Environment.getExternalStorageDirectory().getPath() + dirName + File.separator , fileName);

where dirName is:

String dirName = Environment.getExternalStorageDirectory().getAbsolutePath();

and fileName is:

String fileName = "ee.sqlite";

so I could easily check whether file exist or not using my criteria function.

if (file.exists()){
            Toast.makeText(getApplicationContext(), "found", Toast.LENGTH_SHORT).show();
        }else{
            Toast.makeText(getApplicationContext(), "not found", Toast.LENGTH_SHORT).show();
        }

I like to thank @andru for helping me.

That doesn't seem to make much sense, you're including two times the absolute path to the external storage directory. — RedGlyph, Mar 14 '15 at 15:25

File object can't find the file when there is one

2 Answers2