Book Image

The Java Workshop

By : David Cuartielles, Andreas Göransson, Eric Foster-Johnson
4 (2)
Book Image

The Java Workshop

4 (2)
By: David Cuartielles, Andreas Göransson, Eric Foster-Johnson

Overview of this book

Java is a versatile, popular programming language used across a wide range of industries. Learning how to write effective Java code can take your career to the next level, and The Java Workshop will help you do just that. This book is designed to take the pain out of Java coding and teach you everything you need to know to be productive in building real-world software. The Workshop starts by showing you how to use classes, methods, and the built-in Collections API to manipulate data structures effortlessly. You’ll dive right into learning about object-oriented programming by creating classes and interfaces and making use of inheritance and polymorphism. After learning how to handle exceptions, you’ll study the modules, packages, and libraries that help you organize your code. As you progress, you’ll discover how to connect to external databases and web servers, work with regular expressions, and write unit tests to validate your code. You’ll also be introduced to functional programming and see how to implement it using lambda functions. By the end of this Workshop, you’ll be well-versed with key Java concepts and have the knowledge and confidence to tackle your own ambitious projects with Java.
Table of Contents (20 chapters)

Working with Objects in Java

Objects are to classes what variables are to data types. While classes define the structure and possible actions of a certain data type, objects are actual usable parts of the computer memory containing that data. The action of creating an object is known as making an instance of a class. In a sense, it is like making a copy of the template and then modifying it by accessing its variables or methods. Let's see this in action:

Computer myPC = new Computer( 2.5 );

myPC is the actual object. We would say that myPC is an object of the class Computer in colloquial terms.

The different fields and methods inside the class can be accessed by typing the name of the object followed by a period and the name of the variable or method you want to address. Making any changes to the variables or calling the methods will take effect only within the scope of that object. If you had more objects of the same class in your program, each one of them would have...