Re: Finding other classes in .jar from running program?

From:
Knute Johnson <nospam@rabbitbrush.frazmtn.com>
Newsgroups:
comp.lang.java.programmer
Date:
Thu, 11 Sep 2014 20:51:05 -0700
Message-ID:
<lutqj9$qkh$1@dont-email.me>
On 9/11/2014 18:39, Arne Vajh??j wrote:

On 9/11/2014 9:28 PM, Arne Vajh??j wrote:

On 9/11/2014 9:15 PM, Knute Johnson wrote:

Is there a way given a program running from a .jar file to find the
other classes in the .jar file?


You can ask where a given class is loaded from and if it is a jar
file then you can list the content of the jar file.


Something like:

import java.io.IOException;
import java.util.Enumeration;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

public class Available {
     private static String getLocation(Class<?> clz) {
         return
clz.getProtectionDomain().getCodeSource().getLocation().getPath();
     }
     public static void main(String[] args) throws IOException {
         String jarnam = getLocation(Available.class);
         System.out.println(jarnam);
         JarFile jarf = new JarFile(jarnam);
         Enumeration<JarEntry> e = jarf.entries();
         while(e.hasMoreElements()) {
             JarEntry je = e.nextElement();
             String clznam = je.getName().replace('/', '.');
             if(clznam.endsWith(".class")) {
                 System.out.println(clznam);
             }
         }
         jarf.close();
     }
}

Arne


Thanks Arne, that's exactly what I was looking for. I did have a little
hiccup with the getLocation().getPath(), I'm using Windows and there is
a space character in my path. Apparently getPath() returns a URL
encoded string but the URLDecoder fixed it right up.

Thanks very much,

knute...

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