getCodec method
Retrieves a codec by MIME type.
If mimeType is null, returns an auto-detecting codec.
Throws CodecNotSupportedException if no codec matches.
Implementation
RdfBinaryGraphCodec getCodec(String? mimeType) {
final codec = _registry.getCodec(mimeType);
return codec is RdfBinaryGraphCodec
? codec
: _RdfBinaryGraphCodecWrapper(codec);
}