nftokenTaxon property
nftokenTaxon Indicates the taxon associated with this token. The taxon is generally a value chosen by the minter of the token and a given taxon may be used for multiple tokens. The implementation reserves taxon identifiers greater than or equal to 2147483648 (0x80000000). If you have no use for this field, set it to 0.
Implementation
final int nftokenTaxon;