Insights into Java's popularity

Recently I was involved in a discussion on why Java has become so popular. As a result I did a bit of searching around. If you ask this question (Why has Java become so popular?) to people, the typical answers would be in the line of - Java is platform independent, Ease of use, Object Oriented, Multi-threaded and the like. However there is more to this than just good features of Java.

One of the most important ingredients to Java’s success is the marketing strategy employed by Sun. They did a great job on this one and I mean it in a positive way. Java (or Oak as it was called earlier) was invented for a very different purpose and for a different project. It was meant to network electronic devices. By definition it was expected that there would be varying environments involved, the programs had to be resilient in the face of devices coming on and going off the network and so on. However for whatever reason this idea did not take off and Java was orphaned. Sun probably actually did not know what to do with Java – the project went through many phases of closures and rebirths. However the explosive growth of the internet was round the corner. Java by design was suited to address some of the problems that came with this growth. At this point Sun made a great decision to put Java into the hands of the community across the world while still maintaining just enough control to enforce discipline. This was in a way innovative for the times – the developer community embraced Java like a long lost cousin. Java reached the stage it is today through this partnership. Has Sun made a lot of money in the process, I do not know, but it gave Java a great life ahead.

The other aspect of why Java grew so popular is that it is a dynamic language by design. The fact that Java is interpreted gives the designers the advantage of doing certain things differently. However there is still credit due to them for considering doing things differently. To understand the significance of the dynamism of Java, consider the following. Lets say there is a software system running for a particular purpose. As time progresses the needs of the users change and so do the expectations from this software. How does one add more functionality to this system?

The typical solution for the above problem is to build a new version of the software with additional/changed features. Then replace the older version with new one. The key to note here is that although the new and old versions of the software share the same code base, they are distinctly two different entities. This is where Java’s dynamism can be very helpful. One could build a system in Java that could be extended while on the run. A Java based Application Server is a very good example. We add new functionality (in fact complex new applications themselves) at run time without bringing down the Application Server itself. This of course does not mean that all Java programs are extensible. It just means that Java provides an easy platform. A running Java program can discover new things about code that it encounters for the first time through the mechanism of Reflection. The programmer still has to do the hard work of designing a system that harnesses these capabilities. That said let me also talk about the earlier C/C++ world. What I described above is also possible to be done using shared libraries (or dynamic linked libraries). But it is not as easy to do it – primarily because shared libraries were invented with a different goal in mind.

These two aspects of Java made it popular. Today its very well embraced by many communities and in fact many critical projects bet their money on Java.