我能用USB访问我创建的文件吗

我在这里迷路了。

我使用以下(剥离)代码创建文件:

File dir = getBaseContext().getDir(dirPath, MODE_WORLD_WRITEABLE);
try {
File file = new File(dir, fileName);
FileOutputStream fous = new FileOutputStream(file);
fous.write(data);
fous.flush();
fous.close();
long l = file.length();
Log.i("PpCameraActivity", "File size : " + l);
} catch (IOException e) {
e.printStackTrace();
Toast.makeText(getBaseContext(), "Error while trying to write photo file",  Toast.LENGTH_LONG).show();
}

我可以用logcat验证我的文件似乎是被创建的(它有一个非空的长度)。但当我把我的Android设备连接到我的电脑时,我看不到它。 所以…我的档案在哪里?它是隐藏的吗?擦除?

编辑:我现在正尝试在SD卡上写,具体使用:

File root = Environment.getExternalStorageDirectory();
File jpegFile = new File(root.getAbsolutePath() + "/myApplication/" + filePath);

try {
jpegFile.mkdirs();

FileOutputStream fous = new FileOutputStream(jpegFile);
fous.write(data);
fous.flush();
fous.close();
Log.i("PpCameraActivity", "File written : " + jpegFile.getAbsolutePath());
Toast.makeText(getBaseContext(), "File written : " + jpegFile.getAbsolutePath(), Toast.LENGTH_LONG).show();
long l = jpegFile.length();
Log.i("PpCameraActivity", "File size : " + l);
} catch (IOException e) {
e.printStackTrace();
Toast.makeText(getBaseContext(), "Error while trying to write photo file", Toast.LENGTH_LONG).show();
}

但我在创建fileOutputstream时得到了一个fileNotFoundException…