code: public static String mergePath(String current, String realPath) throws MalformedURLException {
  
  	// get current directory
  	String currDir;
  	if (current == null || current.indexOf('/') == -1) currDir = "/";
  	else if (current.endsWith("/")) currDir = current;
  	else currDir = current.substring(0, current.lastIndexOf('/') + 1);
  
  	// merge together
  	String path;
  	if (realPath.startsWith("./")) path = currDir + realPath.substring(2);
  	else if (realPath.startsWith("/")) path = realPath;
  	else if (!realPath.startsWith("../")) path = currDir + realPath;
  	else {
  	    while (realPath.startsWith("../") || currDir.length() == 0) {
  		realPath = realPath.substring(3);
  		currDir = currDir.substring(0, currDir.length() - 1);
  		int index = currDir.lastIndexOf('/');
  		if (index == -1) throw new MalformedURLException("invalid realpath definition for URL");
  		currDir = currDir.substring(0, index + 1);
  	    }
  	    path = currDir + realPath;
  	}
  
  	return path;
      }
docs: merge to pathes to one
  
  @param current
  @param realPath
  @return
  @throws MalformedURLException