Q&A

How to create an ArrayList in Java?

How to create an ArrayList in Java?

Create one ArrayList of ArrayList myList.

Create two integer variables: arrayListCount to hold the total count of ArrayList and itemCount to hold the total count of strings for each ArrayList.

Ask the user to enter the total number of ArrayList to add.

Ask the user to enter the total elements for each ArrayList.

How do I print array in Java?

How to Print int array in Java. In order to print integer array, all you need to do is call Arrays.toString(int array) method and pass your integer array to it. This method will take care of printing content of your integer array, as shown below.

What is an array list?

An Array List is a list that is characterized as being implemented using an array. This is distinct, for example, from a Linked List which is implemented by linked object references. The intent of the naming is to allow you to pick which one better-suits your needs.

How to get the capacity of the ArrayList in Java?

Java ArrayList do not provide a way to access its current capacity. You can only construct an ArrayList specifying an initial capacity using constructor ArrayList (int initialCapacity) or increase the capacity by calling ensureCapacity ().

How does ArrayList works internally in Java?

ArrayList in Java is a Resizable-array implementation of the List interface.

Internally ArrayList class uses an array of Object class to store its elements.

When initializing an ArrayList you can provide initial capacity then the array would be of the size provided as initial capacity.

How to sort an array in Java?

Java array sort method.

Syntax of using the sort method in Arrays.

An example of sorting an int array.

Demo of sorting elements in descending order.

Sort a string array example.

Sorting a selection of array elements example.

A simple solution for primitive type descending order.

Java Collections sort method.

Syntax of using the Collections sort method.