An script to decompile multiple java classes with CFR Java Decompiler: http://www.benf.org/other/cfr/

decompile-java-classes-cfr

#!/usr/bin/env bash

# USAGE: ./decompile-java-classes.sh -d {cfr jar} -i {input directory} -n {fiel name pattern} -o {output directory}

# Output directory and file name is optional
# File name accepts wildcard such as '*'

OUTPUTDIR="/tmp/decompiled-classes/"
FILE_NAME="*"

SCRIPT_USAGE="USAGE: ./decompile-java-classes.sh -d {cfr jar} -i {input directory} -n {fiel name pattern} -o {output directory}"

export PROCESSED_FILES=0

while getopts "d:i:o:n:" opt; do
  case "$opt" in
    d)
      DECOMPILER=$OPTARG
      ;;
    i)
      INPUTDIR=$OPTARG
      ;;
    n)
      FILE_NAME=$OPTARG
      ;;
    o)
      OUTPUTDIR=$OPTARG
  esac
done

function decompileFile() {

  decompiler="$1"
  file=$2
  outputdir=$3

  java -jar ${decompiler} ${file} --outputdir ${outputdir}

  returnValue=$?

  if [ $returnValue -eq 0 ] ; then
    echo -n "."
  else
    return $returnValue
  fi
}

export -f decompileFile

if [ -z "$INPUTDIR" ] ;
    then
      echo "No input directory supplied";
      echo $SCRIPT_USAGE;
      exit 1;
    elif [ -z "$DECOMPILER" ] ; then
      echo "No decompiler supplied";
      echo $SCRIPT_USAGE;
      exit 1;
    else
      FILES_COUNT=$(find ${INPUTDIR} -type f -name "${FILE_NAME}.class" | wc -l)
      
      echo "There are $FILES_COUNT files to process"

      find ${INPUTDIR} -type f -name "${FILE_NAME}.class" \
        -exec bash -c 'decompileFile "$0" "$1" "$2"' ${DECOMPILER} {} ${OUTPUTDIR} \;

      returnValueFind=$?

      if [ $returnValueFind -eq 0 ] ; then
        echo -ne "\nFiles successfully decompiled in '${OUTPUTDIR}'\n\n"
      else
        echo -ne "\nCFR Decompile failed =(\n\n"
      fi

      exit $returnValueFind;
fi

find . -type f -name "*.class" -exec bash -c 'java -jar cfr-0.151.jar $0 --outputdir decompiled' {} \;
🤷