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From Gregory Shimansky <gshiman...@gmail.com>
Subject Re: [drlvm] DRLVM should accept Java6 classes now
Date Fri, 07 Sep 2007 11:21:34 GMT
Gregory Shimansky wrote:
> Tim Ellison wrote:
>> Yuri Dolgov wrote:
>>>> we can make this constant definable by the build.
>>> That's a great idea. I agree.
>>
>> Would it be too expensive as a runtime check? i.e ask the classlib at
>> start-up if the VM should behave like Java 5 or Java 6, then we don't
>> even have to produce separate VM builds.
> 
> I don't think it would be expensive in any way. This constant 
> CLASSFILE_MAJOR_MAX is currently used only in 2 places, to check that 
> class file version is supported by VM, and to define java.class.version 
> property value on startup.
> 
> This property could be defined by classlib code, and VM would use its 
> value in class loader instead of hardcoded class version.

Hmm now that I think of it there may be a recursion. To get a value of 
java.class.version VM would need to load at least some classes from 
classlib which would require knowing the supported class version of VM 
side. But this property could be supplied by the launcher from the VM 
command line.

Launcher is still a part of classlib so there may be different version 
of for Java5 and Java6.

-- 
Gregory


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