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)

Spawning a new process


In this recipe, we will see how to spawn a new process using ProcessBuilder. We will also see how to make use of the input, output, and error streams. This should be a very straightforward and common recipe. However, the aim of introducing this is to make this chapter a bit more complete and not just to focus on Java 9 features.

 

Getting ready

There is a command in Linux called free, which shows the amount of RAM that is free and how much is being used by the system. It accepts an option, -m, to show the output in megabytes. So, just running free -m gives us the following output: 

We will be running the preceding code from within the Java program.

How to do it...

Follow these steps:

  1. Create an instance of ProcessBuilder by providing the required command and its options: 
        ProcessBuilder pBuilder = new ProcessBuilder("free", "-m");

An alternative way to specify the command and options is as follows:

        pBuilder.command("free", "-m");
  1. Set up the input and output streams...