Book Image

Learn Java 12 Programming

By : Nick Samoylov
Book Image

Learn Java 12 Programming

By: Nick Samoylov

Overview of this book

Java is one of the preferred languages among developers, used in everything right from smartphones, and game consoles to even supercomputers, and its new features simply add to the richness of the language. This book on Java programming begins by helping you learn how to install the Java Development Kit. You will then focus on understanding object-oriented programming (OOP), with exclusive insights into concepts like abstraction, encapsulation, inheritance, and polymorphism, which will help you when programming for real-world apps. Next, you’ll cover fundamental programming structures of Java such as data structures and algorithms that will serve as the building blocks for your apps. You will also delve into core programming topics that will assist you with error handling, debugging, and testing your apps. As you progress, you’ll move on to advanced topics such as Java libraries, database management, and network programming, which will hone your skills in building professional-grade apps. Further on, you’ll understand how to create a graphic user interface using JavaFX and learn to build scalable apps by taking advantage of reactive and functional programming. By the end of this book, you’ll not only be well versed with Java 10, 11, and 12, but also gain a perspective into the future of this language and software development in general.
Table of Contents (25 chapters)
Free Chapter
Section 1: Overview of Java Programming
Section 2: Building Blocks of Java
Section 3: Advanced Java

Packages, importing, and access

As you already know, the package name reflects the directory structure, starting with the project directory that contains the .java files. The name of each .java file has to be the same as the name of the top—level class declared in it (this class can contain other classes). The first line of the .java file is the package statement that starts with the package keyword, followed by the actual package name – the directory path to this file in which slashes are replaced with dots.

A package name and the class name together compose a fully qualified class name. It uniquely identifies the class, but tends to be too long and inconvenient to use. That is when importing comes to the rescue, by allowing specification of the fully qualified name only once, and then referring to the class only by the class name.

Invoking a method of a class...