The example below constructs an empty list of fish, constructs 10 fish and adds them to the list, and then steps through the list asking each fish to move forward.
// Construct a list (initially empty) that could hold fish. ArrayList<AquaFish> fishList = new ArrayList<AquaFish>(); // Construct 10 new fish and add them to the list. for ( int i = 0; i < 10; i++ ) { AquaFish aNewFish = new AquaFish(aqua); fishList.add(aNewFish); aqua.add(aNewFish); // For display purposes } // Move each fish forward, without changing direction. for ( int i = 0; i < fishList.size(); i++ ) { AquaFish aFish = fishList.get(i); aFish.moveForward(); // Or, fishList.get(i).moveForward(); }
(This is a simplified version of code that might appear in the Aquarium Lab Series.)