Revisiting Java

This chapter is added as the refresher course of Java. In this chapter, we will discuss some concepts of Java that will be useful while creating applications in Apache Spark.

This book assumes that the reader is comfortable with the basics of Java. We will discuss useful Java concepts and mainly focus on what is new in Java 8? More importantly, we will touch upon on topics such as:

• Generics
• Interfaces
• Lambda expressions
• Streams