As I thought about writing an operating system, I came across a point that I really couldn't figure out on my own:
Can an operating system truly be written in an Object-Oriented Programming (OOP) Language?
Being that these types of languages do not allow for direct accessing of memory, wouldn't this make it impossible for a developer to write an entire operating system using only an OOP Language?
Take, for example, the Android Operating System that runs many phones and some tablets in use around the world. I believe that this operating system uses only Java, an Object-Oriented language. In Java, I have been unsuccessful in trying to point at and manipulate a specific memory address that the run-time environment (JRE) has not assigned to my program implicitly. In C, C++, and other non-OOP languages, I can do this in a few lines.
So this makes me question whether or not an operating system can be written in an OOP, especially Java.
Any counterexamples or other information is appreciated.
Best Answer
The android backbone is written on top of linux so not really. It is possible to write an Operating System in C++ and there are many ones out there albeit not popular. C++ gives you the OOP concepts you want while still allowing you to do the low level stuff that you need in order to communicate with hardware. C still is the language that most operating systems are written in (with some assembly backbone required) and this is because C is lightweight and personally I find it better just because it removes a lot of the OOP stuff that I find isn't needed to write an operating system (that's just my opinion though).
Technically it is possible to write an operating system in Java in a sense you would need to hook into C/C++ code (I can't remember how to do it in Java but I believe you can) which would in turn call on the assembly required to talk to some of the hardware. The java code would also have to compile directly to machine language instead of the current bytecode scheme that runs on the Java Virtual Machine.
The high level concept of the OS could be done in java but the problem is that a lot of the functionality would have to exist in another form as doing some of the required things for handling data from devices and such cannot easily be accomplished in Java if at all.