Book Image

Transitioning to Java

By : Ken Fogel
Book Image

Transitioning to Java

By: Ken Fogel

Overview of this book

This comprehensive guide will help non-Java developers already using different languages transition from their current language to all things Java. The chapters are designed in a way that re-enforces a developer’s existing knowledge of object-oriented methodologies as they apply to Java. This book has been divided into four sections, with each section touching upon different aspects that’ll enable your effective transition. The first section helps you get to grips with the Java development environment and the Maven build tool for modern Java applications. In the second section, you’ll learn about Java language fundamentals, along with exploring object-oriented programming (OOP) methodologies and functional programming and discovering how to implement software design patterns in Java. The third section shows you how to code in Java on different platforms and helps you get familiar with the challenges faced on these platforms. In the fourth section, you’ll find out how you can manage and package your Java code. By the end of this Java programming book, you’ll have learned the core concepts of Java that’ll help you successfully transition from a different language to Java.
Table of Contents (23 chapters)
1
Part 1:The Java Development Environment
5
Part 2:Language Fundamentals
15
Part 3:GUI and Web Coding in Java
19
Part 4:Packaging Java Code

Creating an object managed by Context Dependency Injection and validated with Bean Validation

Only two Java classes are used in this program, and they are nearly identical to what we used in Chapter 13, Desktop Graphical User Interface Coding with Swing and JavaFX. They are both subject to CDI, and the data class also uses BV. Rather than show the entire code for these beans we saw in Chapter 13, we will only look at what needs to be changed.

FinanceBean

The first annotation, @Named, defines this class as under the control of CDI. Before CDI was widely used, JSF had its own CDI-like implementation that used the @ManagedBean annotation. This is considered obsolete and should no longer be used. The name in the parenthesis, money, is an alias we can use in the expression language:

@Named("money")

Scopes

When an object managed by CDI in a Jakarta application is created or destroyed, and other classes may access it, it is referred to as the Scope. There are the...