FULL PRODUCT VERSION :
java -version
java version "1.7.0_80"
Java(TM) SE Runtime Environment (build 1.7.0_80-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.80-b11, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux Ubuntu 3.2.0-84-generic #121-Ubuntu SMP Tue May 5 18:54:05 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux


A DESCRIPTION OF THE PROBLEM :
Hello,

The assert should be:
        assert this.index < this.input.length;

as the max index is (length-1):


/usr/lib/jvm/java-7-oracle/jre/lib/rt.jar!/sun/reflect/generics/parser/SignatureParser.class

    private char current() {
        assert this.index <= this.input.length;

        try {
            return this.input[this.index];
        } catch (ArrayIndexOutOfBoundsException var2) {
            return ':';
        }
    }

Regards,
Jay


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Look at source code.

ACTUAL -
ArrayIndexOutOfBoundsException

REPRODUCIBILITY :
This bug can be reproduced always.