Collection is one of the most important topics for Java programming. Without the proper knowledge of every collection type in Java, it becomes difficult for you to decide which option to pick in a particular scenario.

This course will give you a great understanding of all collection types available in the Collections Framework like lists, linked lists, sets, and hashmaps. 

After completing this course, you will know how data can be modified within a collection, how to sort a collection, and how it can be made thread-safe. You will also cover the internal working of each Java collection so you can work with them more efficiently.

Collections in Java

We have a list with 3 elements, i.e. [5, 3, 1], and the following code is executed.

`nums.add(6);`

`nums.add(0, 4);`

`nums.remove(1);`

What will be the resulting List?

We have a list with 3 elements, i.e. [5, 3, 1], and the following code is executed.
<code>nums.add(6);</code>
<code>nums.add(0, 4);</code>
<code>nums.remove(1);</code>
What will be the resulting List?

Which of the following commands will be used to fetch the first element from an ArrayList named `nums`?

Which of the following commands will be used to fetch the first element from an ArrayList named <code>nums</code>?

Which of the following is the correct syntax to get the last element from an ArrayList named `nums`?

Which of the following is the correct syntax to get the last element from an ArrayList named <code>nums</code>?

Given the nums ArrayList with the values [1, 4, 3, 2], which of the following t statements removes the value 2 from the list?

Choose all that apply.

Given the nums ArrayList with the values [1, 4, 3, 2], which of the following t statements removes the value 2 from the list?
Choose all that apply.

Given an ArrayList with the following elements [3, 4, 7, 5, 9], what will be the output of the below statement?

`System.out.println(list.remove(0));`

Given an ArrayList with the following elements [3, 4, 7, 5, 9], what will be the output of the below statement?
<code>System.out.println(list.remove(0));</code>

Which of the following interfaces should we use if we need more than one type of sorting logic for our objects?

Which of the following interfaces should we use if we need more than one type of sorting logic for our objects?

Which of the following methods is present in the Comparable interface?

Which of the following methods is present in the Comparable interface?

In the `Collections.sort(List<T> o)` method, T should implement which interface?

Here `T` represents the type of object present in ArrayList.

In the <code>Collections.sort(List&lt;T&gt; o)</code> method, T should implement which interface?
Here <code>T</code> represents the type of object present in ArrayList.

Let's Begin

Lists in Java

LinkedList in Java

CopyOnWriteArrayList in Java

Sets in Java

TreeSet in Java

HashMap In Java

TreeMap in Java

LinkedHashMap in Java

Additional Map Implementations

Arrays Class

Collections Class

Quiz: ArrayList