Why is the compiler platform independent while JVM is platform dependent?

[Aashu Mahajan]

Hello Guys,
I could not understand Why is the compiler platform independent while JVM is platform dependent?
Please could anybody explain it??
Thanks

[Ankit Garg]

The JVM converts the instructions in the byte code (generated by the compiler) into machine level instructions (sort of) so it needs to know the OS. The JVM makes your code platform independent but there is not another layer between the JVM and the OS to make the JVM platform independent. The JVM has to interact with the OS but the compiler has to generate instructions for the JVM which are the same for all OS...

[Bear Bibeault]

The compiler is not platform independent. Each platforms needs its own compiler. The bytecode produced by the compiler is what is platform independent.

[Aashu Mahajan]

Ankit Garg wrote:The JVM converts the instructions in the byte code (generated by the compiler) into machine level instructions (sort of) so it needs to know the OS.

suppose If a java application developed on any platform and compiled it, the JVM makes the byte code from the compiled program and for that it communicates with the OS on which the code compliled and when that byte code is ported to different platform or different OS so their JVM (on which the byteCode is ported) again communicated with the byteCode to run it, is it???
Please remove my confusion.

[Ulf Dittmer]

The compiler is not platform independent.

I'm not so sure about that. javac, for example, consists largely of Java classes that I'm fairly certain are the exact same ones on all platforms. javac.exe is a native starter app, but I don't think that does much in the way of compiling. The most platform-specific thing the compiler does would seem to be reading and writing files from/to the file system.