unmarshal, как правильно парсить атрибуты xml с помощью JAXB

Есть 2 класса, в которых я описал теги.

        import javax.xml.bind.annotation.*;

    @XmlRootElement(name = "request")
    @XmlAccessorType(XmlAccessType.FIELD)
    public class AuthorizeRequest extends RequestHeader {

        private To to;
        private Receipt receipt;

        public AuthorizeRequest() {
        }

        public static class To {

            public To() {
            }

            @XmlElement(name = "account-number")
            private String accountNumber;
            @XmlElement(name = "amount")
            private Double amount;

            public To(String accountNumber, Double amount) {
                this.accountNumber = accountNumber;
                this.amount = amount;
            }

            @Override
            public String toString() {
                return "To{" + "accountNumber=" + accountNumber + ", amount=" + amount + '}';
            }

        }

        public static class Receipt {

            public Receipt() {
            }

            @XmlElement(name = "datetime")
            private String datetime;
            @XmlElement(name = "receipt-number")
            private String receiptNumber;

            public Receipt(String datetime, String receiptNumber) {
                this.datetime = datetime;
                this.receiptNumber = receiptNumber;
            }

            @Override
            public String toString() {
                return "Receipt{" + "datetime=" + datetime + ", receiptNumber=" + receiptNumber + '}';
            }
        }

        public void setAdditionalData(String accountNumber, Double amount, String datetime, String receiptNumber) {
            this.to = new To(accountNumber, amount);
            this.receipt = new Receipt(datetime, receiptNumber);
        }

        @Override
        public String toString() {
            return "AuthorizeRequest{" + "to=" + to + ", receipt=" + receipt + '}';
        }
    }

и второй класс:

import javax.xml.bind.annotation.*;

/**
 * Created by urmat.ukeshov on 30.06.2017.
 */
@XmlAccessorType(XmlAccessType.FIELD)
public class RequestHeader {
    @XmlElement(name = "request-type")
    private String requestType;

    @XmlElementRef(name = "extra")
    private Login login = new Login();
    @XmlElementRef(name = "extra")
    private Password password = new Password();

    @XmlAccessorType(XmlAccessType.FIELD)
    @XmlRootElement(name = "extra")

    public static class Login {

        @XmlAttribute(name = "name")
        private String login = "login";
        @XmlValue
        private String loginValue;

        public String getLogin() {
            return login;
        }

        public void setLogin(String login) {
            this.login = login;
        }

        public String getLoginValue() {
            return loginValue;
        }

        public void setLoginValue(String loginValue) {
            this.loginValue = loginValue;
        }

        @Override
        public String toString() {
            return "Login{" + "login=" + login + ", loginValue=" + loginValue + '}';
        }
    }

    @XmlAccessorType(XmlAccessType.FIELD)
    @XmlRootElement(name = "extra")
    public static class Password {

        @XmlAttribute(name = "name")
        private String password = "password-md5";
        @XmlValue
        private String passwordValue;

        public String getPassword() {
            return password;
        }

        public void setPassword(String password) {
            this.password = password;
        }

        public String getPasswordValue() {
            return passwordValue;
        }

        public void setPasswordValue(String passwordValue) {
            this.passwordValue = passwordValue;
        }

        @Override
        public String toString() {
            return "Password{" + "password=" + password + ", passwordValue=" + passwordValue + '}';
        }
    }

    @XmlElement(name = "transaction-number")
    private String transactionNumber;

    public String getRequestType() {
        return requestType;
    }

    public void setRequestType(String requestType) {
        this.requestType = requestType;
    }

    public String getTransactionNumber() {
        return transactionNumber;
    }

    public void setTransactionNumber(String transactionNumber) {
        this.transactionNumber = transactionNumber;
    }

    public Login getLogin() {
        return login;
    }

    public void setLogin(Login login) {
        this.login = login;
    }

    public Password getPassword() {
        return password;
    }

    public void setPassword(Password password) {
        this.password = password;
    }

    public void setLoginPassword(String login, String password) {
        this.login.setLoginValue(login);
        this.password.setPasswordValue(password);
    }

    @Override
    public String toString() {
        return "RequestHeader{" + "requestType=" + requestType + ", login=" + login + ", password=" + password + ", transactionNumber=" + transactionNumber + '}';
    }
}

и класс обработчик:

import model.AuthorizeRequest;

import javax.xml.bind.*;
import java.io.StringReader;

public class Main {

    public static void main(String[] args) throws JAXBException {

        String xml = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n" +
                "<request>\n" +
                "\t<request-type>1</request-type>\n" +
                "\t<extra name=\"login\">login</extra>\n" +
                "\t<extra name=\"password-md5\">password</extra>\n" +
                "\t<transaction-number>5435345345345</transaction-number>\n" +
                "\t<to>\n" +
                "\t\t<account-number>543543534534</account-number>\n" +
                "\t\t<amount>12.0</amount>\n" +
                "\t</to>\n" +
                "\t<receipt>\n" +
                "\t\t<datetime>1201564878451420</datetime>\n" +
                "\t\t<receipt-number>5435345345345435</receipt-number>\n" +
                "\t</receipt>\n" +
                "</request>";


        try {
            StringReader reader = new StringReader(xml);
            JAXBContext jAXBContext = JAXBContext.newInstance(AuthorizeRequest.class);
            Unmarshaller unmarshaller = jAXBContext.createUnmarshaller();
            AuthorizeRequest authorizeRequest = (AuthorizeRequest) unmarshaller.unmarshal(reader);
        } catch (JAXBException ex) {
            ex.printStackTrace();
        }
    }

}

Проблема заключается в том, что когда я произвожу unmarshal, получаю null значения из внутреннего класса Password, а его значения записываются в переменные класса Login.

Просьба помочь - как правильно парсить через JAXB атрибуты xml?

Источник: https://ru.stackoverflow.com/questions/690388/unmarshal-%D0%BA%D0%B0%D0%BA-%D0%BF%D1%80%D0%B0%D0%B2%D0%B8%D0%BB%D1%8C%D0%BD%D0%BE-%D0%BF%D0%B0%D1%80%D1%81%D0%B8%D1%82%D1%8C-%D0%B0%D1%82%D1%80%D0%B8%D0%B1%D1%83%D1%82%D1%8B-xml-%D1%81-%D0%BF%D0%BE%D0%BC%D0%BE%D1%89%D1%8C%D1%8E-jaxb