[java] Upgrade to ASM7 for JDK 11 support

[markpritchard]

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PR Description:

Remove ASM7_EXPERIMENTAL flag since ASM7 has been released.

PMD 6.10.0 passes the ASM7_EXPERIMENTAL flag to asm, which fails on asm 6.2.1 - ClassVisitor enforces only stable ASM per https://gitlab.ow2.org/asm/asm/blob/master/asm/src/main/java/org/objectweb/asm/ClassVisitor.java#L69

Upgrading PMD to use the recently released ASM 7.0 library and replacing ASM7_EXPERIMENTAL with ASM7 works.

[pmd-test]

	1 Message
📖	This changeset introduces 0 new violations and 0 new errors, removes 0 violations and 0 errors. Full report

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[adangel]

Thanks, looks good!

Just a remark/question:

PMD 6.10.0 passes the ASM7_EXPERIMENTAL flag to asm, which fails on asm 6.2.1 - ClassVisitor
enforces only stable ASM per https://gitlab.ow2.org/asm/asm/blob/master/asm/src/main/java/org/objectweb/asm/ClassVisitor.java#L69

Since PMD 6.10.0 uses asm 6.2.1, passing ASM7_EXPERIMENTAL should still work and JDK 11 support should not be broken.
Of course, when we upgrade asm, we need to change this API flag (like you did).

Did you experience any problems with JDK 11 and PMD 6.10.0 so far?

[markpritchard]

Oops, sorry @adangel - I meant to say fails on asm 7

I haven't seen any issues at all with PMD 6.10.0 on JDK 11 (or with JDK 11 in general).

Thanks again for all your great work!

Cheers,

Mark