This chapter dealt with various concepts of Java and more particularly topics around generics and interfaces. We also discussed new features introduced in Java 8 such as Lambda expressions and streams. Introduction to the default method in Java 8 was also covered in detail.

In the next chapter, we will discuss the installation of Spark and Scala. We will also discuss Scala's REPL and the Spark UI along with exposure of Spark's REST API for working with Spark jobs, Sparks componentsm, and various configuration parameters.