StringChecksumAccessor
class StringChecksumAccessor : public ChecksumAccessor {
StringChecksumAccessor(const BString& checksum);
StringChecksumAccessor::StringChecksumAccessor(const BString& checksum)
StringChecksumAccessor::GetChecksum(BString& _checksum) const
new (std::nothrow) StringChecksumAccessor(fChecksum),