FULL PRODUCT VERSION :
java version "9-ea"
Java(TM) SE Runtime Environment (build 9-ea+167)
Java HotSpot(TM) 64-Bit Server VM (build 9-ea+167, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Linux hera 4.8.0-46-generic #49-Ubuntu SMP Fri Mar 31 13:57:14 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

A DESCRIPTION OF THE PROBLEM :
The source code in java.base/java.util.regex.Pattern.java lines 785 to 794 states:

     * Regular expression modifier values. Instead of being passed as
     * arguments, they can also be passed as inline modifiers.
     * For example, the following statements have the same effect.
     * <pre>
     * RegExp r1 = RegExp.compile("abc", Pattern.I|Pattern.M);
     * RegExp r2 = RegExp.compile("(?im)abc", 0);
     * </pre>
     *
     * The flags are duplicated so that the familiar Perl match flag
     * names are available.

However these Flags Pattern.I, Pattern.M and so on do not exist. RegExp.compile() does not exist either.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Look into the source code.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Comment rework or removed.

REPRODUCIBILITY :
This bug can be reproduced always.