You're going to have to implement a timer to control the reload rate, or else your player is going to be able to shoot at any rate they want. Have a variable check the current time to the reload time and the last shot time, then you'll be good to go.

Since you are talking about eclipse and keylisteners I assume you are coding in Java, right? Responding to key presses are a simple key-listener and there are great examples on them in "The Java tutorial" at suns page.
Rendering stuff(bullets) is also covered in the tutorials.

About the shooting part, I wouldprobably do it something like this:

A bullet class that contains the position, direction and possible damage and velocity too.

A bullet manager class that manages all the bullets, updates and draws them etc.

The key listener would call specific functions in the player to make it use the selected weapons.

From there on it is up to the player/weapon to decide when to shoot. A shotgun would spawn 3 bullets in a widespread manner and only react to keydown messages. A smg would spawn 1 bullet each 0.20 seconds while the key is down.

edit: beaten