The term “Introduction to Java” refers to the fundamental knowledge of the popular, adaptable, and object-oriented Java programming language. Java, which was created by Sun Microsystems in 1995 and subsequently purchased by Oracle Corporation, is platform-independent, meaning that programs created with it can run on any device that has a Java Virtual Machine (JVM).
Key Features of Java
1. Platform Independence: Made possible by the JVM and the “Write Once, Run Anywhere” (WORA) principle.
2. Object-Oriented: Encapsulates data and behavior by concentrating on objects and classes.
3. Robust and Secure: Features like exception handling, memory management (via garbage collection), and security APIs ensure reliable and secure code execution.
4. Multithreaded: Supports concurrent programming for tasks like data processing or UI updates.
5. Rich API: Offers a vast library of classes and methods for networking, I/O, GUI development, and more.
Components of Java
1. Java Development Kit (JDK): This is basically your all-in-one developer toolkit. It comes with a compiler (called javac), libraries, and a few command-line tools that help you write and build Java programs.
2. Java Runtime Environment (JRE): Once you’ve written your code, the JRE takes over. It provides the setup needed to run Java programs — including the JVM and the required libraries.
3. Java Virtual Machine (JVM): This is the engine that actually runs your Java code. It reads the compiled bytecode and makes sure your program works the same way on any operating system. That’s what gives Java its famous “write once, run anywhere” feature.
Why Learn Java?
Versatility and Practical: You can use Java to build almost anything — from web apps and enterprise software to Android mobile applications and even IoT-based systems.
Huge Community Support: Java has a massive global developer community. That means plenty of tutorials, libraries, and frameworks to help you solve problems faster.
Scalable and Reliable: Whether you’re creating a small utility app or a large enterprise system, Java grows smoothly with your project’s needs.
If you’re new to Java, start by learning the basics — things like syntax, variables, loops, and object-oriented programming concepts.
Once you’ve got the fundamentals down, move on to popular frameworks such as Spring, Hibernate, or JavaFX to start building real-world applications.