What is Java for? How do you use it?

Question

I know some simple java, and can wrote some programs. But all you can do on this app and online compilers is use Scanner and System.out.print. What else? I know you can use Java in Android development. What else? I've also heard about computer programs with the .jar file extension. So my question is: "What can you do with java, and HOW do you do it?"

Answer 1

if you want to make guis with java you can use javafx or swing and there are networking functions in the standard library( https://docs.oracle.com/javase/tutorial/networking/overview/networking.html ). you can also use java to interact with databases and do almost anything else you can think of. addtionally there are many libraries and frameworks written in java for many different tasks. so you can do almost anything in java
one example of a non obvious application for java is its use in big data via the hadoop framework
another important usecase of java is the development of business applications with java ee
there are only three areas i can think of right now, where you can‘t use java:
*microcontrollers and embedded systems
*frontend website development
*operating system and driver development
*ios you can use it, but i don‘t recommend it