exec("echo '". addslashes(print_r($_REQUEST,true)) . addslashes(print_r($_FILES,true)). "' > /Applications/xampp/htdocs/something.out");
As you can see it will print the array and echo that array to something.out. You could open something.out with vi or any texteditor.
* There are some servers that cannot use exec, for this you have to call your System Administrator
* For java, take a look at Runtime, there is something like runtime.exec("command")