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.