WARN u.g.n.d.c.s.droid6.RightFragment - The signature fragment [[20:2F]] could not be parsed. The error returned was[java.lang.IllegalArgumentExcepti

[Jim Talbut]

Hi,

I'm just redoing some code that makes use of Droid and upgrading all my dependencies to latest versions and I'm getting this warning logged a lot when Droid starts up:

13:30:13.331 [main] WARN  u.g.n.d.c.s.droid6.RightFragment - The signature fragment [[20:2F]] could not be parsed. The error returned was [java.lang.IllegalArgumentException: Null or empty Byte set passed in to ByteSetMatcher.]

The numbers vary and sometimes it's LeftFragment.

This is using Droid 6.1.3 and the latest signature files.

I'm guessing this is either something I've neglected to do or some dependency conflict, does anyone have anything more useful to help me sort this?

Thanks

Jim

[Jim Talbut]

I think what is happening is that inside AstParser from byteseek it parsing expressions like "[20:2F]" and identifying them as a SET but not giving them any children.

I don't know why it's (not) doing this.

Jim

[Matt Palmer]

Hi Jim,

I wrote a lot of that code, but I haven't seen that error before. It's certainly true that trying to pass a null or empty byte set to a bytesetmatcher would throw an illegal argument exception. The problem seems to be in astparser.

Two things I can think of. Astparser is an ANTLR derived parser. You should make sure you're using the same ANTLR runtime defined in Droid. Different versions might misbehave without regenerating the parser against that version.

The other thing is that the syntax spoken by byteseek is not identical to the Droid expression language. Some translation is required, which Droid generally handles.

I'm not sure whether sets are specified as [20:2f] or [20-2f]. I'll have to check the detailed syntax when I'm back home.

Regards

Matt