Book Image

Java 11 Cookbook - Second Edition

By : Nick Samoylov, Mohamed Sanaulla
Book Image

Java 11 Cookbook - Second Edition

By: Nick Samoylov, Mohamed Sanaulla

Overview of this book

For more than three decades, Java has been on the forefront of developing robust software that has helped versatile businesses meet their requirements. Being one of the most widely used programming languages in history, it’s imperative for Java developers to discover effective ways of using it in order to take full advantage of the power of the latest Java features. Java 11 Cookbook offers a range of software development solutions with simple and straightforward Java 11 code examples to help you build a modern software system. Starting with the installation of Java, each recipe addresses various problem by explaining the solution and offering insights into how it works. You’ll explore the new features added to Java 11 that will make your application modular, secure, and fast. The book contains recipes on functional programming, GUI programming, concurrent programming, and database programming in Java. You’ll also be taken through the new features introduced in JDK 18.3 and 18.9. By the end of this book, you’ll be equipped with the skills required to write robust, scalable, and optimal Java code effectively.
Table of Contents (18 chapters)

Creating a functional interface

In this recipe, you will learn how to create and use a custom functional interface when none of the standard interfaces in the java.util.function package satisfies the requirements.

Getting ready

Creating a functional interface is easy. One just has to make sure there is only one abstract method in the interface, including methods inherited from other interfaces:

@FunctionalInterface
interface A{
void m1();
}

@FunctionalInterface
interface B extends A{
default void m2(){};
}

//@FunctionalInterface
interface C extends B{
void m3();
}

In the preceding example, interface C is not a functional interface because it has two abstract methodsm1(), inherited from interface A, and its own method...