The java programming language is becoming more and more popular each day. It is the language without which one cannot even hope to a land a job thesedays. But has somebody even wondered how this language came about? There are many stories about, many books have been written. Here is my version (not approved by Sun Microsystems).
The java programming language originated in Indonesia. It was meant to be usedby the tourists that visit that country each year. Why would tourists want to use computer? Well, these are no ordinary tourists. They are rich tourists. Havethey not been rich, they would not travel half way around the world to visit this place. Most people would be content to see just what is available near by. Forexample, if you are a texan living in Dallas, you will visit the stockyards or may be the trinity river park. If you live in New Orleans area, you would see st. mary?sbayou. Once in your lifetime, one will probably visit Hawaii or Niagara. But going to Indonesia and its islands, Bali, Java, etc is not for the ordinary people. Anyway, coming back to the question why these tourists need to usecomputer programs. They go there not just to have fun and also get some workdone in a fun atmosphere as these people are very important people.
From the very start java was supposed to be computer independent. That means ifyou write a program in java in one computer, it should run in all computers. This was necessary because tourists bring all kinds of computers with them.Some bringWindows machine, some Apple mackintosh. Some of the affluent ones bringSun server workstations or even a super computer.
Before starting to create java they also sought to see if there have similar stuff done already. Even though they could find none, they found they can uselots of feature from some existing laguages. One such language they found was C++. C++ was an advancement over the language called C. In fact, ideas ofC++ was already hidden in C. In that language, one can increment a variable, say i, by applying the ++ operator e.g. i++. This would increase the value ofthe variable i by one. If i had a value of 5, it would make it 6, etc. What a vision!
Anyway, coming back to C++, it made an important advancement over C by introducing the idea of a class. To understand class, one has to undestand structure which was already used in C. The structure is a group of variables.For example, you have a name, an address, age etc. for any person. In stead ofusing them separately, in C one can group them together and call it a person.The creator of C++ said there is no need to expose these variables (name, address, etc) to the outside world. They said these details should be hiddenfrom the outside world. They called this concept encapsulation.
Another important contribution of C++ was the concept of inheritence. This concept can be best explained by example. Let?s go back to the example of the person. A person isvery general concept. There can be many different kinds of persons, e.g doctors,lawyers, teachers, or just a bum! But each of these people have a name, an address, age etc. Even a bum has all these. The creator of C++ thought one candefine a base class call person and other classes can be derived from it. In plain english, this would mean, a doctor is special kind of person, lawyer isanother special kind of person. Now the common attributes of all these kinds of people can be put in the person class and special attributes can be put in
the derived classes, e.g.hospital for the doctor, court for the lawyer, and nothing for the bum.
But C++ was still complex with things like pointers, memory leak and multipleinheritence. The pointer concept was taken from C and it was very messy! The pointer is special type of variablethat points to other variables. Since there was no guidelines as to how to use these pointers, it was very easy loose track of them. In a typical two thousand lines program, one would frequently end up with hundredes of pointers pointingto thousands, some of them are pointers and some just plain variables. Needlessto say this made a large program extremely difficult to read and when the programmer left for another company, they would have no other choice thanto just throw away his program! It was sometimes necessary to do this even when the programmer was around and very much alive. This is because the pointers he created inside his program had taken a life of their own and defy every attempt to predict how the program should behave.Memory management was also another weak point of C and C++. The programmer wasresponsible for cleaning up the memory their program would allocate and use.Failure to do so will result in a crash of the whole computer.
Multiple inheritence, though sparingly used, wasanother feature of C++ which made a programmer?s life miserable. It, however, had its use, especially in job interviews. This one question, they thought, helped them separate the wheat from the chaff.
But C++ still had some nice and simple features, like inheritence, encapsulation, etc. They are something one can describe in plain english,something one can explain to a layman. So the creator of java decided to takethe good features of inherience, encapsulation, and polymorphism from C++, while discarding the bad features such as multiple inherience, pointers etc. The memory management was improved in java where the programmer will not be held responsible for memory management. Theycan clean up after themselves if they want to get extra credit, but they do not need to. Needless to say all these was great news to the tourists in Indonesia!
Java introduced lot of clarity in notations too. For example, in C++ they would say class doctor:person to mean doctor is derived from person.It is obviously very cryptic. The same situation can be expressedin java as class doctor extends person , which is much easier to understand. But there are few awkward stuff in java too especially when someonesays class bum extends person (my last bum joke)!
Java made an important contribution in the graphical user interface (GUI) area.C++ was really lacking in expertise here. They visual C++, but worked only onwindows environment. But it did not work in UNIX systems or mackintoshes. Justlike other features of java, this was also supposed to be platform independent.This was further necessary because one can put some little GUI on a web page which can be views over the internet. And one cannot control what kind of computers other will have.
After a while, it was necessary to call programs from one computer to anothercomputer. To do this, they created J2EE. I am not sure how they cameup with the name J2EE. The ?J? of J2EE, of course, means ?Java?, and I can bereasonably sure ?2? stands for ?To?. But I do not know what the ?EE? part is allabout, probably some kind of extension. Or at this point they ran out of names to think of. So they decided tohave one of those just another vague acronyms.
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Copyright ? 2003 Gautam Dev. All rights reserved
Source: http://www.mwstm.com/2012/03/13/History-of-Java/
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