array of arraylists java code example
Example 1: how to make an array of arraylists in java
ArrayList [] myList = (ArrayList[]) new ArrayList[4];
Example 2: arraylist of arraylist
public static void main(String[] args) {
ArrayList> outer = new ArrayList>();
ArrayList inner = new ArrayList();
inner.add(100);
inner.add(200);
outer.add(inner); // add first list
inner = new ArrayList(inner); // create a new inner list that has the same content as
// the original inner list
outer.add(inner); // add second list
outer.get(0).add(300); // changes only the first inner list
System.out.println(outer);
}