grep-like utility written in Java

jrep is a command-line grep-like utility written in Java.
Features:
  -- Java regular expressions
     (https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html)
  -- Support for RE2J
     (https://github.com/google/re2)
  -- POSIX options (excluding -E and -G)
     (http://pubs.opengroup.org/onlinepubs/009604499/utilities/grep.html)
  -- most GNU grep(1) options
     (https://www.gnu.org/software/grep/)
  -- Extensions over GNU grep(1):
     options -O, -2 and -8
Documentation:
  -- https://github.com/cheusov/jrep/blob/master/scripts/jrep.pod
       or
  -- man page after installation