Concerning the data classes in Project Amber, work is in progress. It proposes to provide developers with a simplified method for modeling data, introducing special classes with the record keyword. The state of a data class could be captured by using the class header, which is in stark contrast to the existing Plain Old Java Objects (POJOs).

In this chapter, we'll cover the following topics:

• An introduction to data classes
• The need for data classes, and their limitations
• The aggregate and exploded forms of data classes
• Pattern matching with data classes
• Inheritance with abstract data classes and interfaces
• Adding variables and methods
• Overriding default behaviors