Book Image

Java 9 with JShell

By : Gaston C. Hillar
Book Image

Java 9 with JShell

By: Gaston C. Hillar

Overview of this book

The release of Java 9 has brought many subtle and not-so-subtle changes to the way in which Java programmers approach their code. The most important ones are definitely the availability of a REPL, known as JShell, which will make experiments and prototyping much more straightforward than the old IDE-based project-led approach. Another, more subtle change can be seen in the module system, which will lead to more modularized, maintainable code. The techniques to take full advantage of object-oriented code, functional programming and the new modularity features in Java 9 form the main subjects of this book. Each chapter will add to the full picture of Java 9 programming starting out with classes and instances and ending with generics and modularity in Java.
Table of Contents (23 chapters)
Java 9 with JShell
Credits
About the Author
Acknowledgement
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Index

Using feedback from domain experts


Now, it is time to have a meeting with our domain expert, that is, someone that has an excellent knowledge of 2D geometry. We can use the UML diagram to explain the object-oriented design for the solution. After we explain the different classes that we will use for abstracting the behavior, the domain expert explains to us that there are many shapes that have something in common and that we can generalize the behavior even further. The following six shapes are regular polygons:

  • An equilateral triangle (the EquilateralTriangle class) has three sides

  • A square (the Square class) has four sides

  • A regular pentagon (the RegularPentagon class) has five sides

  • A regular hexagon (the RegularHexagon class) has six sides

  • A regular octagon (the RegularOctagon class) has eight sides

  • A regular decagon (the RegularDecagon class) has ten sides

Regular polygons are polygons that are both equiangular and equilateral. All the sides that compose a regular polygon have the same length...