In the earlier stages of computer science, Pascal, C, C++ and Java have not existed yet.
Due to the fact that the primitive computers have different brand, model and hardware properties, the former software developers could not execute a program in different computers that they have coded it for a specific computer. In addition to that, software developers had to develop the distinctive programs according to the computer that the code would be executed in.
In order to handle those kinds of difficulties, Assembly Language was revived and then other advanced programming languages such as C, C++, Pascal, Cobol, Fortran.
The advancement of new programming languages provides huge advantages for developers and except a few standards, regardless of its programming language, a program was able to be executed in all different operating systems thanks to Compiler.
But this benefit causes some of its own drawbacks. A program could be run only in the operating system which is compiled in, that is to say, the issue of platform dependency shows up. In case of changing operating system, the program cannot be run and in order to run it, the compiler must be run by an applicable compiler to the operating system.
Platform Dependency: a program that is compiled in the Windows Operating System cannot be run in any other operating system such as Linux or Macintosh.
The advancement of computer science technology has caused to be created different brand and model operating systems that have, unlike properties, so the problem has grown up.
The need for a programming language that is platform-independent was essential.
Electrical home appliances manufacturer Sun Microsystems wished to create a new programming language in order for household appliances to be used easier and they realised that the best way of that is to design a common platform and then in 1995, Sun Microsystems’ Developer James Gosling created “Java” language which can be run as platform-independent.
A virtual machine called JVM(Java Virtual Machine) that can be work with different operating systems and hardware created and brought it into use free of charge.
Thus, programs coded with Java is converted to a running machine language which works in JVM java compiler.
The developers who wish to make java applications may install JVM easily in their operating system. In order to do so, all they need to do is to download a program called JRE(Java Runtime Environment) from the internet.
After installed JRE in your computer, you are able to run entire java programs. When developers wish to run their java programs JRE created a JVM and this case occurs only at the moment that the developer wishes to run the java code. JVM is not a program that can work by itself, It only awakes when a java code wished to run. After the running finish, the JVM will be erased from the memory.
Due to these reasons, Java is able to run in all platforms and it takes only fast and effective features of C and C++ languages.
- Can produce programs that could be run in computers
- Internet Applications
- XML Applications
- Can produce programs that could be run in mobile phones
- Can produce programs that could be run in-game machines
- Can produce programs that could be run in household appliances