Book Image

Introduction to Programming

By : Nick Samoylov
Book Image

Introduction to Programming

By: Nick Samoylov

Overview of this book

Have you ever thought about making your computer do what you want it to do? Do you want to learn to program, but just don't know where to start? Instead of guiding you in the right direction, have other learning resources got you confused with over-explanations? Don't worry. Look no further. Introduction to Programming is here to help. Written by an industry expert who understands the challenges faced by those from a non-programming background, this book takes a gentle, hand-holding approach to introducing you to the world of programming. Beginning with an introduction to what programming is, you'll go on to learn about languages, their syntax, and development environments. With plenty of examples for you to code alongside reading, the book's practical approach will help you to grasp everything it has to offer. More importantly, you'll understand several aspects of application development. As a result, you'll have your very own application running by the end of the book. To help you comprehensively understand Java programming, there are exercises at the end of each chapter to keep things interesting and encourage you to add your own personal touch to the code and, ultimately, your application.
Table of Contents (21 chapters)

What are JVM processes?

As we have established already in Chapter 1, Java Virtual Machine (JVM) on Your Computer, JVM does not know anything about the Java language and source code. It only knows how to read Byte Code. It reads the bytecodes and other information from .class files, interprets it (transforms it into the sequence of binary code instructions specific to a particular microprocessor, where JVM is running), and passes the result to the computer that executes it.

While talking about it, programmers often refer to JVM as JVM instance or process. This is because every time a java command is executed, a new instance of JVM is launched, dedicated to running the particular application in a separate process with the allocated memory size (default or passed in as the command option). Inside this JVM process, multiple threads are running, each with their own allocated memory...