J2ME : How to get SDCard's available Free Space

I am building J2ME application, where I want to get size of avail开发者_如何学Goable free space on SDCard and on Phone internal storage.

FileConnection fc = (FileConnection) Connector.open("file:///SDCard/");

long total = fc.totalSize();

long used = fc.usedSize();

long free = total - used;