Initialize an Array of ArrayList [duplicate]

Answer 1

Okay after comment, I thought well... your right why not.

Figured it out.

ArrayList[] test = new ArrayList[4];

test[3] = new ArrayList();
test[3].add("HI");

System.out.println(test[3].get(0));

Though I will be honest, I am not really sure WHY this works.

Once you assign the first item of test as a new Collection, it will only allow all other items in the array to be that type. So you couldn't do

test[3] = new ArrayList();
test[2] = new HashSet();