code: @Override
      public InputStream getInputStream() throws IOException {
          if (closed) {
              throw new IllegalStateException("JarURLConnection InputStream has been closed");
          }
          connect();
          if (jarInput != null) {
              return jarInput;
          }
          if (jarEntry == null) {
              throw new IOException("Jar entry not specified");
          }
          return jarInput = new JarURLConnectionInputStream(jarFile
                  .getInputStream(jarEntry), jarFile);
      }
docs: Creates an input stream for reading from this URL Connection.
  
  @return the input stream
  
  @throws IOException
  if an IO error occurs while connecting to the resource.