code: protected InputStream getSegmentInputStream(InputStream baseIn, String segment) throws IOException
     {
        JarInputStream jarIn = new JarInputStream(baseIn);
        JarEntry entry = null;
  
        while (jarIn.available() != 0)
        {
           entry = jarIn.getNextJarEntry();
  
           if (entry == null)
           {
              break;
           }
  
           if (("/" + entry.getName()).equals(segment))
           {
              return jarIn;
           }
        }
  
        throw Messages.MESSAGES.jarUrlConnectionUnableToLocateSegment(segment, getURL().toExternalForm());
     }
docs: Retrieve the <code>InputStream</code> for the nesting
  segment relative to a base <code>InputStream</code>.
  
  @param baseIn The base input-stream.
  @param segment The nesting segment path.
  
  @return The input-stream to the segment.
  
  @throws java.io.IOException If an I/O error occurs.