Java files can be a bit tricky at times. Most of the time, after you have downloaded and saved the java file on your pc, windows tend to change the icon & extension of the file into a .zip.

And this will led to those not familiar with this issue to extract the file. Once that is done, you will see a lot of folders and files. This is not the right way but ofcourse theres a way to get around this. Heres what you should do instead;

First, on your PCs, launch Windows Explorer and then select

Tools>Folder Options>View and "un-tick" the Hide extensions for known file type.

Now only can you see the full extension of a file and change the .zip into .jar and send it to your phone.