Overview:
checkJvmVersion（） function code as below （istribution/distribution-karaf/target/assembly/bin/karaf）：
checkJvmVersion() {

1. echo "`$JAVA -version`"
   VERSION=`"$JAVA" -version 2>&1 | egrep '"([0-9].[0-9]\..[0-9])."' | awk ' {print substr($3,2,length($3)-2)}

   ' | awk '

   {print substr($1, 3, 3)}

   ' | sed -e 's;\.;;g'`

2. echo $VERSION
   if [ "$VERSION" -lt "80" ]; then
   echo "JVM must be 1.8.0 or greater"
   exit 1;
   fi
   }
   The egrep regular expression "([0-9].[0-9]\..[0-9])." is not exact. The first dot(.) doesn't escape and the subexpression [0-9] should use [0-9]+ replaced for the first two, because if java version like this "1.10._111"， this regular expression will failed.In summary, the egrep regular expression "([0-9].[0-9]\..[0-9])." should be "([0-9]\.[0-9]\..[0-9])."
   Steps to Reproduce: null
   Actual Results: null
   Expected Results: null
   Build Date & Hardware:
   Fri Mar 3 17:08:47 CST 2017 PC Linux
   Additional Builds and Platforms: null
   Additional Information: null