Java is by far one of the most popular programming languages, and you would have heard and read this in almost every Java tutorial. Java is so popular for many reasons. For example, it is open source, powerful, easy to learn and implement (to some extent), modular, object oriented, has a very huge developer community and support groups, and the list just grows. Also, one another major reason is, it is a “write once, run anywhere” programming language. This means that you can write a Java program on one platform, and then you can run it on any other platform. How does that work? We’ll see that later.
Wikipedia’s definition of Java is something like this, “Java is a general-purpose, concurrent, class-based, object-oriented computer programming language that is specifically designed to have as few implementation dependencies as possible. “ Java is a unique programming language in that it does not run natively on any platform. It creates its own run time environment, called the “Java Run-time Environment” (JRE), which is designed to run on any platform. The Java code that you write is converted into byte code after compilation, which runs in this JRE on a “Java Virtual Machine” (JVM). This JVM is like a computer inside your computer which is designed to run that Java applications you write.
James Gosling
Unlike some of the other programming languages, Java is not a very old language. Java was first released to developers in 1995, by Sun. The development of Java started in 1991. James Gosling, an engineer at Sun Microsystems, originally developed Java.
The evolution of Java led to the birth of various versions of Java. What started with the Java Standard Edition (J2SE), is now divided into Java Enterprise Edition (J2EE), Java Mobile Edition (J2ME), and many others. And all these editions have their own applications in the concerned fields. Now, let’s have a look at some of the characteristics of Java.
- Object Oriented. This is one of the major advantages of using Java. Almost everything is Java is an object. You can define your own classes or import classes from other packages. This makes Java a lot easier to implement and work with.
- Secure. With public-key encryption, Java is a very secure programming language with which you can develop highly secure distributed applications.
- Platform independent. As already mentioned, Java is a write once, run anywhere programming language. Since Java creates a JVM for itself, it can run on any platform. You just need to provide it the appropriate JRE for that platform, and your compiled code will run just fine.
- Architecture neutral. Sometimes, being platform independent is not enough. You need architecture neutral code as well to run on different hardware. Any code you write in Java is converted into an architecture neutral byte code. So you don’t have to worry about that other computer of yours which runs on a different processor.
- Portable. The Java Compiler is written in ANSI C, and Java is architecture neutral and platform independent. These features make Java highly portable.
- Multi-threaded. Most of the times, you need your code to have multiple threads, as the application may demand it. Java makes it easy to create threads in your application, and make you application more robust and responsive.
This list can get a lot lengthier. So let’s stop it here. Now, enough of theory, and let’s start building our first Java application. But first, you will need to download a couple of software tools and set up and environment for your Java application to run. We will see how to do this in the next post.