java - How to use more than one language for a project? -

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we see huge projects written in more 1 language example facebook written in php , c++, , android operating system written in c,c++ , java. in following links on right side more 1 languages written in front of "written in"

android=http://en.wikipedia.org/wiki/android_(operating_system)

facebook=http://en.wikipedia.org/wiki/facebook

are there compilers doing this?

sometimes (facebook) have system of many different interacting programs, each of can written in different language, , running on different machines. sure complex website facebook involves many pieces written in many different mainstream , homespun "languages".

other times (android) have single entity in pieces written in different languages combined. i'm on simplifying bit, if think it, compilers compile down machine code, , linker can combine pieces.

in reality, it's more complex, , many languages interpreted rather compiled. combine languages have complex runtime systems java, python, ruby, etc 1 program, there specific, point-to-point solutions each case. example, java native interface (jni) standard mechanism embedding java c , c++ programs.


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