This is the best way to download .jar files with Opera
¤¤>Open your Opera Mini browser,select the file you want to download.
¤¤>Press 1 on the download link or long press the link
¤¤>A pop up menu will appear,select Open In New Tab and stop loading that page sticky before Opera calls on your default browser to download the .jar file.
¤¤>Now copy the link in the address bar.
¤¤>Select archive converter
¤¤>Select contest to Zip
¤¤>Then paste the link in the enter URL field.
¤¤>Press convert file and refresh the page to download your file.
¤¤>Then you can easily convert it into .jar file by using apps.