Java
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I originally approached Java as “just another programming language,” which in many senses it is. But as time passed and I studied it more deeply, I began to see that the fundamental intention of this language is different from all the other languages I have seen. - Bruce Eckel, Thinking in Java (the Java Bible).
Java is everywhere! Basically anywhere you encounter the internet, whether mobile apps, operating systems, embedded systems, real-time software, data mining, cloud computing, you name it. The thing is, the user usually doesn’t notice this, because Java is mostly used to write server-side applications, usually with no front-end at all. And users mainly see the front-end of a system. That’s what the front ends are for.
I guess this means that you chose the right language to learn, and that you stumbled upon this wee lil’ webshite of mine. Bear with me as I tell you some basics today.
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class MyClass
{
public static void main(String[ ] args) {
System.out.println("Java is the number 1 in enterprise software");
}
}
This means that the heavy applications that large companies work with are written in Java.
For example, most server applications in the financial world are written in Java. The IT departments of many banks use Java to write back-end and front-end systems for electronic payments, settlement and confirmation of payments, data processing and so on.
The server side of many web apps is also built in Java. You come across Java in the web apps of government agencies, educational and healthcare institutions and other organisations.
Tools for programmers
Software development tools are also quite often written in Java.
Java is a major player in big data
Hadoop and many other big data technologies also work with Java. The same applies to ElasticSearch, HBase and Accumulo. Engineers use Java for scientific applications and mathematical calculations.
Android and mobile apps
And as you probably already know, you can use Java to program mobile apps. Android is a whole Java-friendly environment. What language do you think most Android apps are written in?”
- Minecraft, the most popular sandbox game in the world, was written in Java by Marcus ‘Notch’ Persson.
- Google+ (the whole server side) and many other Google services: in Java.
- The best development tools, such as Eclipse and IntelliJ IDEA. (You will be introduced to IDEA shortly.)
- The Facebook web app for Android… And just about any other Android app out there.
- Amazon web services. So when you buy something from Amazon, you’re using Java. Still nice to know.
- Most Netflix services are built with Java.
- Android’s operating system (its user interface) is written in Java along with C and C++.
- Many Tesla Motors applications are written in Java.
- And finally: the server side of CodeGym is also made with Java (of course you never thought)!
Lambda expression
A lambda expression is a piece of code in Java that can be treated as an object of a functional interface. It is a way to create anonymous functions in Java. A lambda expression consists of two parts: a list of parameters and an expression or block of code. These functions can be used in many contexts where a functional interface object is needed, such as in the Stream API.
READ: Lambda
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