how to find the jar file containing a class definition? [closed]

Answer 1

I use jarscan. It is an executable jar file that can recursively search an entire folder structure for jars that contain the class that you are looking for. It searches by class name, package name or regex.

Answer 2

(This is an improvement over the script I had in previous versions of the answer as it produces much cleaner output at the price of some awk special/ugly quoting.)

I've built a script (findinjars) which does just that.

#!/usr/bin/env bash
if [[ ($# -ne 1) && ($# -ne 2) ]]
then
    echo "usage is $0 <grep pattern to look for in 'jar tvf' output> [<top-of-dir-tree> or, if missing, current dir]"
else
    THING_TO_LOOKFOR="$1"
    DIR=${2:-.}
    if [ ! -d $DIR ]; then
        echo "directory [$DIR] does not exist";
        exit 1;
    fi
    find "$DIR" -iname \*.jar | while read f ; do (jar tf $f | awk '{print "'"$f"'" "  " $0}' | grep -i "$THING_TO_LOOKFOR") ; done
fi

you can then invoke it with:

$findinjars a.b.c.d.Class [directoryTreeRoot or, if missing, current dir]

or just

$findinjars partOfClassName [directoryTreeRoot or, if missing, current dir]

Dot characters in the fully qualified class name will be interpreted in the regexp sense of 'any character' but that's not a big deal since this is a heuristics utility (that's why it's case-insensitive too BTW). Usually I don't bother with the full class name and just type part of it.

Answer 3

I usually employ bash for that: grep -lr "ClassName" . The trick is that names aren't encoded in any way. You can open jar file in text editor and you'll see them. (You can even include package name in search query.)

I suspect, there's some windows equivalent too.

Answer 4

The best and easiest way is to use the JAD Decompiler. And yes, its an ECLIPSE PLUGIN !

Download and save the plugin in any location on your machine.

The plugin contains the following files:

1. A temp folder
2. A jad.exe file
3. A *net.sf.jadclipse_3.3.0.jar* JAR plugin
4. A Readme

Perform the following steps:

1. Copy the JAR plugin to the plugins folder of eclipse folder
2. Open eclipse. Goto Window >> Preferences >> Java >> JADClipse >> Path to Decompiler.
3. Give the path of jad.exe
4. Restart Eclipse

Now select any class and press F3.

The .class file will automatically decompile and display the contents !

Answer 5

I ran into the same problem countless times, so I wrote a little tool to find them.

A simple command line: findclass MyClass -classpath ...

It searches directories, jar, zip, war and ear files for your class. I wrote it a few years back and use it all the time. I thought others might find it useful too so I uploaded onto github.

It's freely available to download: https://github.com/eurozulu/Findclass/tree/master/dist

If you want to look at the source, it's in the same site: https://github.com/eurozulu/Findclass/tree/master

If you like it, just let me know to give me that warm comfy feeling :)

Answer 6

I recently created a tool to search class , packages and libraries. You can try it http://javasearch.buggybread.com/. Click on the framework and it will help you locate dependency information ( jar , pom).