Getting 'root" permission for Android App -

i know how can root permission android app? there app out there in android market?

i tried out below line of code list out files nothing happened

process process = runtime.getruntime().exec(new string[] { "su", "-", "root"}); 

i tried give test_factory permission in manifest file got error "permitted system app"

how can make app system app?

i want started these stuff (make app if possible root permission) on appreciated. in advance :)

first: note can execute shell commands using su (= can use shell commands root, not java code).

second: not sure if applies su apps out there, message of su on phone:

usage: su [options] [--] [-] [login] [--] [args...]  options:     --daemon                      start su daemon agent     -c, --command command         pass command invoked shell     -h, --help                    display message , exit     -, -l, --login                pretend shell login shell     -m, -p,     --preserve-environment        not change environment variables     -s, --shell shell             use shell instead of default /system/bin/sh     -u                            display multiuser mode , exit     -v, --version                 display version number , exit     -v                            display version code , exit,                                   used exclusively superuser.apk   

this means: have run su -c something (or su -c - root, rootis default anyway). equal su on linux systems, except daemon-thing, there no daemon ahndling su calls on regular linux systems.

if other su commands behave differently (which possible), it's more secure open stream shell, execute su, evaluate it's return code, proceed execute other commands, execute exit.