private Map<String,String> fetchPropertiesFromUpdateServer(@Nullable Version version) throws IOException {
  String requestUrl=combinePaths(updateServerEndpoint,"repository/properties",getName() + (version != null ? "/" + version.toString() : ""));
  try {
    Map m=asMap(transport.doGet(requestUrl));
    return Collections.checkedMap(m,String.class,String.class);
  }
 catch (  JsonParseException e) {
    throw new IOException(e);
  }
}

private Map < String , String > fetchPropertiesFromUpdateServer ( @ Nullable Version version ) throws IOException { String requestUrl = combinePaths ( updateServerEndpoint , "repository/properties" , getName ( ) + ( version != null ? "/" + version . toString ( ) : "" ) ) ; try { Map m = asMap ( transport . doGet ( requestUrl ) ) ; return Collections . checkedMap ( m , String . class , String . class ) ; } catch ( JsonParseException e ) { throw new IOException ( e ) ; } }
if version is not specified then the properties of the latest stable version will be retrieved
