code: protected String rebuildQueryStringWithoutParameter(String source, String ... params){
  		if (source==null || source.length()==0)
  			return "";
  		if (params == null || params.length==0)
  			return source;
  		HashSet<String> paramsSet = new HashSet<String>(params.length);
  		paramsSet.addAll(Arrays.asList(params));
  		String[] tokens = StringUtils.tokenize(source, '&');
  		StringBuilder ret = new StringBuilder();
  		for (String t : tokens){
  			String[] values = StringUtils.tokenize(t, '=');
  			if (paramsSet.contains(values[0]))
  				continue;
  			if (ret.length()>0)
  				ret.append('&');
  			ret.append(values[0]).append('=').append(values.length >= 2 ? values[1] : "");
  		}
  		return ret.toString();
  	}
docs: Rebuilds query string from source.
  @param source original source.
  @param params parameters that should be included in the query string.
  @return