chapter one

1 Java technology and environment

 

Exam objectives covered in this chapter

What you need to know

[1.1] Describe Java Technology and the Java development environment

[1.2] Identify key features of the Java language

 

It is an exciting time to learn and level-up on programming in Java. A general-purpose computer language, you’ll find Java code everywhere - from sensors or embedded software, to mobile devices. From gaming software, desktop applications, to Open source libraries and frameworks. You can find Java programs written for navigation systems, web applications, to complex multithreaded Enterprise applications. Java applications or services span across a plethora of industries like banking, finance, health, education, media, insurance and domains like IoT, mobile, Security, AI, ML, frameworks, databases, and many more.

The term ‘Java’ has multiple meanings depending on the context it is used it in (by the end of this chapter, you’d know enough to correct someone if they are using it incorrectly). Apart from using ‘Java’ to refer to a programming language, it is also used to refer to its editions, like, Standard Edition (SE), Micro Edition (ME), or Enterprise Edition (EE). You would also notice usage of Java in refence to Java’s Virtual Machine (JVM), Java’s Runtime Engine (JRE) or Java’s Development Kit (JDK). Talking about JDK, you could hear mention of OpenJDK, OracleJDK, AdoptOpenJDK and JDKs by other companies.

1.1   Java Technology – what, where and why

1.1.1   How did it start

1.1.2   Java’s release cadence

1.2   Java’s magic – Java Virtual Machine and bytecode

1.3   Development Tools

1.4   Demystifying acronyms in the Java world

1.4.1   Java SE, JSR and JCP

1.4.2   JDK, JVM and JRE

1.5   My first Java program - Conquer the world

1.6   Features of Java

1.6.1   Irrelevant features and components of Java

1.7   Looking ahead

1.8   Summary

1.9   Sample exam questions

1.10   Answers to sample exam questions