public void setMessageData(String messageData) {
        this.messageData = messageData;
    }
<p>
The data for which a MAC is under generation. This value must be hexBinary.
</p>

@param messageData
       The data for which a MAC is under generation. This value must be hexBinary.
aws-java-sdk-paymentcryptographydata/src/main/java/com/amazonaws/services/paymentcryptographydata/model/GenerateMacRequest.java