Gain insights into Java Collections Framework. Delve into lists, sets, and hashmaps. Learn about data modification, sorting, thread-safety, and internal workings for efficient usage.

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

TreeMap is a class in the `java.utils` package that stores the keys in sorted order. Some of the features of **TreeMap** are:

1. The entries in **TreeMap** are sorted in the natural ordering of its keys.

2. It does not allow null keys, however there can be null values.

3. The TreeMap is not thread-safe, although it can be made thread-safe using the `synchronizedMap()` method of the **Collections** class.

Since a **TreeMap** stores the keys in sorted order, the objects that we are storing in the **TreeMap** should either implement the **Comparable** interface or we should pass a **Comparator** while creating the **TreeMap** object. 

Let's look at the creation and insertion of TreeMap.

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

TreeMap: Creation and Insertion