code: public static String relativePath(String base,
                                        String pathSpec,
                                        String path )
      {
          String info=pathInfo(pathSpec,path);
          if (info==null)
              info=path;
  
          if( info.startsWith( "./"))
              info = info.substring( 2);
          if( base.endsWith( "/"))
              if( info.startsWith( "/"))
                  path = base + info.substring(1);
              else
                  path = base + info;
          else
              if( info.startsWith( "/"))
                  path = base + info;
              else
                  path = base + "/" + info;
          return path;
      }
docs: Relative path.
  @param base The base the path is relative to.
  @param pathSpec The spec of the path segment to ignore.
  @param path the additional path
  @return base plus path with pathspec removed