Please stop incrementing the classfile version number when there are no format changes

John Rose john.r.rose at
Fri Oct 11 19:58:59 UTC 2019

On Oct 11, 2019, at 12:39 PM, Remi Forax <forax at> wrote:
>> P.S.  Mike your point about a bundled ASM is a very good one.
>> The lack of a bytecode spinner in the JDK is long-standing tech. debt,
>> on which the interest rate has risen (because the payments are the
>> same but now come due every six months).   Who’s on the hook to
>> fix this?  All of us, really; it’s the OpenJDK.  Starting up a JEP would
>> make a good place to gather information about options and requirements.
>> — John
> The problem of bundling it in the JDK is that it forces people that maintains libraries that want to read/write the newest classfiles to be compatible with the newest JDK unlike ASM which only requires Java 5.
> So it will solve the problem of Mike but will cause problems to others that have not yet migrated their libraries to the newest JDK.

Yep.  This is the sort of observation that we’ll want to accumulate around a JEP.

(BTW, I didn’t say “lack of ASM” I said “lack of a bytecode spinner”, in JDK.
And putting one in wouldn’t be a cure-all either.  There are advantages to having
ASM decoupled from the JDK, as well as disadvantages.)

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