How to read/write external USB storage on Android?

Question

I am currently making an app that needs to be able to read from and write to a USB flash drive connected via a USB OTG adapter. Is there an easy way to access this storage via standard Java.io.File APIs? This app is only going to be run on a rooted Motorola Xoom running Android 4.2.2. Any suggestions would be appreciated.

Solution

USB Drives get mounted to your device just like an SDCard does essentially*.

The mount path usually resides at:

/storage/usb0/

I have not used this on many devices other then my Droid running CyanogenMod, your device may very. You can smiply use a file manager to explore this path. The directories will still exist even if there is no mount path, so you will be able to determine the path.

Comments

[Nathan Walters]

Thanks, this worked perfectly with a small modification. For future reference of anyone viewing this thread, the path for a Moto Xoom is /storage/usbdisk0/.

[Bobs]

Is not there any method that returns its exact path on every device?