java

* Java

	<b>This is an outline on how to support Java, actual
	implementations of ideas like this can be found <a href="http://radio.weblogs.com/0109845/">here</a></b>


	It would be interesting to support the Java language as part
	of the Mono project.  

	You have to think of Java as various pieces: Java the
	language and Java the virtual machine.  

	It is possible to compile Java to .NET, as shown by the
	Microsoft J# compiler.   We could then allow the migration of
	Java applications to the Mono runtime. 

** Native compiler

	Although a native compiler can be built, and probably should be
	built using an existing compiler, a short term solution is to 
	build a translator from Java class files to the ECMA CIL images.

	This has the advantage that we can use an existing and tested
	Java compiler to generate the code, and then we can use an automated
	code compiler that compiles Java VM bytecodes to CIL bytecodes.

** The translator.

	It would be interesting to write a semantic translator that
	converts java byte codes into CIL opcodes.  This is possible
	because the Java byte codes are a subset of the CIL ones.

	A semantic tree needs to be constructed (very much in the
	spirit of what is done in mono_analize_stack in
	<tt>mono/mono/jit/jit.c</tt>.  Once such a semantic tree is
	constructed, we could generate the equivalent Java code.

	This has a number of interesting side effects: people can
	continue to use their existing Java compilers to compile their
	code, and a simple tool that converts their .class files into
	a .NET assembly can be used.

** Libraries

	We could translate the GNU Classpath libraries with the above
	tools to provide the Java runtime required to host into the
	Mono runtime.  Some special treatment would be required for
	core data types like integers, arrays and strings, and of
	course reuse where possible existing classes from .NET to make
	them compatible.

** JILC - Java to IL Compiler

	This is an attempt to make the java bytecode available for the
	.NET environment.

	The project attempts to generate the IL code / bytecode from the
	compiled java class files. It has reached the stage of code-generation.
	The issues that needs to be addressed is the mapping of java objects
	to the IL objects, eg: java.lang.String to System.String.

	Gaurav Vaish and Abhaya Agarwal are currently leading this project.
	The project is currently hosted at <a href="http://sourceforge.net/projects/jilc">SourceForge.Net</a>.
	The official home page of the project is 
	<a href="http://jilc.sourceforge.net">http://jilc.sourceforge.net</a>.