code: @Nullable
    public static InputStream getResourceAsStream (@Nonnull final ClassLoader aClassLoader,
                                                   @Nonnull @Nonempty final String sPath)
    {
      ValueEnforcer.notNull (aClassLoader, "ClassLoader");
      ValueEnforcer.notEmpty (sPath, "Path");
  
      // Ensure the path does NOT starts with a "/"
      final String sPathWithoutSlash = _getPathWithoutLeadingSlash (sPath);
  
      // returns null if not found
      final InputStream aIS = aClassLoader.getResourceAsStream (sPathWithoutSlash);
      return StreamHelper.checkForInvalidFilterInputStream (aIS);
    }
docs: Get the input stream of the passed resource using the specified class
  loader only. This is a sanity wrapper around
  <code>classLoader.getResourceAsStream (sPath)</code>.
  
  @param aClassLoader
  The class loader to be used. May not be <code>null</code>.
  @param sPath
  The path to be resolved. May neither be <code>null</code> nor empty.
  Internally it is ensured that the provided path does NOT start with
  a slash.
  @return <code>null</code> if the path could not be resolved using the
  specified class loader.