Before attempting to create a file path to the SD card in an Android application, your Java code must first check that an SD card is mounted on the device, as this is not always the case.

As would creating the jar file and deleting the manifest file. I'm looking for a jar command line - what switches, options, what parameters - would create a jar file without a manifest file.

Explore Java for mobile app development: how to create Android apps in 2025 with this reliable programming language.