// Try to make a real entry for the promised version.
e = makeEntry(e.version(), computeValue(type));
} finally {
// Whether computeValue throws or returns normally,
// be sure to remove the empty entry.
e = map.finishEntry(this, e);
}
if (e != null)
return e.value();
// else try again, in case a racing thread called remove (so e == null)
}