Book Image

Learn Java with Projects

By : Dr. Seán Kennedy, Maaike van Putten
5 (3)
Book Image

Learn Java with Projects

5 (3)
By: Dr. Seán Kennedy, Maaike van Putten

Overview of this book

Learn Java with Projects stands out in the world of Java guides; while some books skim the surface and others get lost in too much detail, this one finds a nice middle ground. You’ll begin by exploring the fundamentals of Java, from its primitive data types through to loops and arrays. Next, you’ll move on to object-oriented programming (OOP), where you’ll get to grips with key topics such as classes, objects, encapsulation, inheritance, polymorphism, interfaces, and more. The chapters are designed in a way that focuses on topics that really matter in real-life work situations. No extra fluff here, so that you get more time to spend on the basics and form a solid foundation. As you make progress, you’ll learn advanced topics including generics, collections, lambda expressions, streams and concurrency. This book doesn't just talk about theory—it shows you how things work with little projects, which eventually add up to one big project that brings it all together. By the end of this Java book, you’ll have sound practical knowledge of Java and a helpful guide to walk you through the important parts of Java.
Table of Contents (22 chapters)
1
Part 1: Java Fundamentals
9
Part 2: Object-Oriented Programming
15
Part 3: Advanced Topics

Summary

In this chapter, we started by explaining that Java uses block scope. A block is delimited by { }. A variable is visible from the point of declaration to the closing } of that block. As blocks (and therefore, scopes) can be nested, this means that a variable defined in a block is visible to any inner/nested blocks. The inverse is not true, however. A variable declared in an inner block is not visible in an outer block

Conditional statements enable us to make decisions and are based on the evaluation of a condition resulting in true or false. The if statement allows several branches to be evaluated. Once one branch evaluates to true and is executed, no other branch is evaluated. An if statement can be coded on its own without any else if or else clause. The else if and else clauses are optional. However, if an else clause is present, it must be the last clause. We saw how a complex if example can lead to code verbosity.

We briefly discussed packages and the Scanner class...