Amazon AWS running java code on separate screen

When an Java program is run on the same window as the EC2 login, when the window closes, the program also terminates. To avoid this, the program can be run on separate screen. the commands is below

$screen

Now even if the window is closed, the program continue to run.

Now after logging in again, if want to access the screen, can type in the below

$screen -r

references:
http://cs.smith.edu/dftwiki/index.php/Tutorial:_So_you_want_to_run_your_code_on_Amazon%3F