public int compareTo(Object obj) {
            if (!(obj instanceof CmapSubtable)) {
                return -1;
            }
            
            CmapSubtable cms = (CmapSubtable) obj;
            if (platformID < cms.platformID) {
                return -1;
            } else if (platformID > cms.platformID) {
                return 1;
            } else {
                if (platformSpecificID < cms.platformSpecificID) {
                    return -1;
                } else if (platformSpecificID > cms.platformSpecificID) {
                    return 1;
                } else {
                    return 0;
                }
            }
        }