Looks for .jar file in a path that conflict with a reference .jar

conflicting_jars.sh

#!/bin/bash
# Looks for jars in a path that conflicting with a reference jar.
# usage: ./conflicting_jars.sh <reference.jar> <path/to/other/jars>

function abspath() {
    # from http://stackoverflow.com/questions/3915040/bash-fish-command-to-print-absolute-path-to-a-file
    # generate absolute path from relative path
    # $1     : relative filename
    # return : absolute path
    if [ -d "$1" ]; then
        # dir
        (cd "$1"; pwd)
    elif [ -f "$1" ]; then
        # file
        if [[ $1 == */* ]]; then
            echo "$(cd "${1%/*}"; pwd)/${1##*/}"
        else
            echo "$(pwd)/$1"
        fi
    fi
}

function normpath() {
  tr "/" "_"
}

DIR=`mktemp -d`
echo "writing output to '$DIR'"
echo

BASEJAR=$1
NORMPATH_BASEJAR=`abspath $BASEJAR | tr "/" "_"`
BASEJAR_CLASSLIST="$DIR/$NORMPATH_BASEJAR.classlist"
jar tf "$BASEJAR" | grep ".class" > "$BASEJAR_CLASSLIST"

JARS=`find $2 -name "*.jar" -print`
for JAR in $JARS
do
  NORMPATH_JAR=`abspath $JAR | tr "/" "_"`
  if [ $NORMPATH_JAR != $NORMPATH_BASEJAR ]
  then
    CLASSLIST="$DIR/$NORMPATH_JAR.classlist"
    jar tf $JAR | grep ".class" > $CLASSLIST
    JOINCOUNT=`join $CLASSLIST $BASEJAR_CLASSLIST | wc -l`
    if [ $JOINCOUNT -gt 0 ]
    then
      echo $JAR
      echo "class overlap: $JOINCOUNT"
      echo
    fi
  fi
done