fun verify(txId: SecureHash): Boolean
Function to verify a SignableData object's signature. Note that SignableData contains the id of the transaction and extra metadata, such as DLT's platform version. A non-null partialMerkleTree implies multi-transaction signing and the signature is over the root of this tree.
txId - transaction's id (Merkle root), which along with signatureMetadata will be used to construct the SignableData object to be signed.
InvalidKeyException - if the key is invalid.
SignatureException - if this signatureData object is not initialized properly,
the passed-in signatureData is improperly encoded or of the wrong type,
if this signatureData algorithm is unable to process the input data provided, etc.
IllegalArgumentException - if the signature scheme is not supported for this private key or if any of the clear or signature data is empty.