I am talking about the major implementation platform o开发者_JAVA技巧f these platforms.
For Java, the JVM itself is written in C++, probably with a little C or even assembler sprinkled in. The Standard API library, on the other hand, is written almost entirely in Java (with a few native methods implemented in C or C++).
The JVM provided by Sun (Hotspot) is written in C++, although parts of the standard Java library is written in Java as well.
The same goes for .NET. The VM and core libraries (interfacing with the underlying platform and native libraries) are written in C++ , the rest is written in C#.
I'm not sure about the dot net framework, but the jvm is build using a combination of c and java, see also the sources for yourself:
http://download.java.net/jdk6/source/
The bulk of the .Net framework is written in C#. Evidence for this would be Microsoft's Rotor project, which is basically the source code for much of the .Net framework. However, the core libraries are written in C++, including the virtual machine itself and the libraries that interface directly with the operating system.
As for Java, it is much the same as .Net in the way it is programmed.
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