How to Create an Array of Arraylists

How can I create an Array of ArrayLists?

As per Oracle Documentation:

"You cannot create arrays of parameterized types"

Instead, you could do:

ArrayList<ArrayList<Individual>> group = new ArrayList<ArrayList<Individual>>(4);

As suggested by Tom Hawting - tackline, it is even better to do:

List<List<Individual>> group = new ArrayList<List<Individual>>(4);

How to create an array of ArrayLists in java?

You're creating an array of null references, so you need to initialize each of them to a new ArrayList<SMS>():

for (int i = 0; i < count; i++) {
    lists[i] = new ArrayList<SMS>();
}

Create an array of ArrayListString elements

You cannot create an array of a generic type.

Instead, you can create an ArrayList<ArrayList<String>>.

Array of ArrayLists in java

I would use a hash map:

HashMap<Character, ArrayList<String>> letters  = new HashMap<Character, ArrayList<String>>();

Then you can add words by doing:

ArrayList<String> words = new ArrayList<String>();
words.add(word);
letters.put("A", words); 

Understanding array of ArrayLists

Because you are initializing an array not the ArrayList
Look at this:

ElementType [] name = new ElementType[size];

Here your element type is ArrayList

Look at this site:Array of ArrayList

Arrays inside a Arraylist

Looks like you want to create a 2-dimansional integer array.

I assume you have a special use case in which you need a primitive array ob ArrayList-Objects.

Anyways you can create such a thing like any other primitive array
like

ArrayList<Integer>[] test = new ArrayList[2];

and access/set it by index..

test[0] = new ArrayList<Integer>();

You also can fill the array on init...

ArrayList<Integer>[] test = new ArrayList[] {
        new ArrayList<Integer>(),
        new ArrayList<Integer>(),
        new ArrayList<Integer>()
};

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