I'm working on a 2D game for Android using LibGDX in Java. In my game I got lots of enemies, bullets and other stuff. I hold a hash map, which every cell holds a reference to an array list of that kind of objects. For example:
Enemies = [enemy1,enemy2,enemy3]
Bullets = [bullet1,bullet2] etc...
In my render() loop I run with an iterator on the hash map and run through all the objects in every array list, calling each one's update() method.
I wonder, would it be faster holding a linked list to every kind of objects instead of array list and running through that linked list?