Java
A statically-typed, object-oriented language dominant in enterprise backends.
CurrentintermediateFull course available
Overview
Java is a statically-typed, compiled (to bytecode, run on the JVM) language built around object-oriented programming. It remains foundational in large enterprise systems, Android development (historically), and any environment prioritizing long-term stability and strong tooling.
- What it is
- A statically-typed, object-oriented language that compiles to JVM bytecode.
- Why it's used
- For its strong typing, mature tooling, backward compatibility, and the JVM's performance and portability ('write once, run anywhere').
- Where it fits
- A common choice for large backend systems (often via Spring Boot) and historically for native Android development. This platform's Java Programming Foundations course teaches the language itself, from the JVM execution model through generics, streams, and JUnit testing.
Core concepts
- Classes and objects
- Interfaces
- Static typing
- Exceptions
- Collections (List, Map, Set)
Example
Every Java program lives inside a class, and types are declared explicitly (String name) -- the compiler checks them before the program ever runs.
public class Greeter {
public static String greet(String name) {
return "Hello, " + name + "!";
}
}Common use cases
- Enterprise backend systems
- Android apps (alongside Kotlin)
- Large-scale distributed systems
Project ideas
- A simple class hierarchy modeling a real-world domain (e.g. shapes, employees) using interfaces