Gets JDK version used on each JAR file stored in $LIB_HOME

jar_jdk_versions.sh

#!/bin/bash

LIB_HOME=/path/to/lib/*.jar

version['45.3']=1.1
version['46']=1.2
version['47']=1.3
version['48']=1.4
version['49']=5
version['50']=6
version['51']=7
version['52']=8

for JAR_FILE in $LIB_HOME
do
    echo "- $(basename $JAR_FILE)"
    rm -rf jar_content
    unzip -qq -n $JAR_FILE -d jar_content
    v=$(javap -verbose $(find . -type f -name '*.class' | sort -n | head -1) | grep major | tr -d '[a-z] +:')
    echo -e "  Java ${version[$v]}\n"
done