// works for both java.util-wrapped maps as well as our own
static <A, B> Map<A, B> unwrapSynchronizedMap(Map<A, B> map) {
  if (eqOneOf(shortClassName(map),
    "SynchronizedMap",
    "SynchronizedSortedMap",
    "SynchronizedNavigableMap"))
    ret (Map) get_raw(map, 'm);
  ret map;
}