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

Java **TreeSet** class implements the **Set** interface that uses a tree for storage. It inherits the **AbstractSet** class and implements the **NavigableSet** interface.

Some of the features of **TreeSet** are:

1. **TreeSet** does not allow duplicate elements.
2. **TreeSet** class doesn't allow null elements.
3. Since elements are stored in a tree, the access and retrieval times are quite fast in a **TreeSet**.
4. The elements are stored in ascending order in a **TreeSet**.




Let's look at TreeSet creation and insertion.

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

TreeSet: Creation and Insertion