创建和Java Web Launcher，从Web服务器下载文件，然后运行它

Im Making a Game for windows, and i wanna do an java web app that download the files from the server, put in the player computer and when its done, start it, its not very big, its around 30 mbs, and i plan too to download only the basic files, and while the game goes on download the extra files,. it should run everything unattended. the files would be compressed in 7-zip, in the unatended SFX format. but i dont know how, not even if its possible, if someone know and give some directions thanks. i Already Program Java, Basic java.Im Making a Game for windows, and i wanna do an