public String getValidationDomain() {
        return this.validationDomain;
    }
<p>
The base validation domain that will act as the suffix of the email addresses that are used to send the emails.
This must be the same as the <code>Domain</code> value or a superdomain of the <code>Domain</code> value. For
example, if you requested a certificate for <code>site.subdomain.example.com</code> and specify a
<b>ValidationDomain</b> of <code>subdomain.example.com</code>, ACM sends email to the domain registrant,
technical contact, and administrative contact in WHOIS and the following five addresses:
</p>
<ul>
<li>
<p>
admin@subdomain.example.com
</p>
</li>
<li>
<p>
administrator@subdomain.example.com
</p>
</li>
<li>
<p>
hostmaster@subdomain.example.com
</p>
</li>
<li>
<p>
postmaster@subdomain.example.com
</p>
</li>
<li>
<p>
webmaster@subdomain.example.com
</p>
</li>
</ul>

@return The base validation domain that will act as the suffix of the email addresses that are used to send the
        emails. This must be the same as the <code>Domain</code> value or a superdomain of the
        <code>Domain</code> value. For example, if you requested a certificate for
        <code>site.subdomain.example.com</code> and specify a <b>ValidationDomain</b> of
        <code>subdomain.example.com</code>, ACM sends email to the domain registrant, technical contact, and
        administrative contact in WHOIS and the following five addresses:</p>
        <ul>
        <li>
        <p>
        admin@subdomain.example.com
        </p>
        </li>
        <li>
        <p>
        administrator@subdomain.example.com
        </p>
        </li>
        <li>
        <p>
        hostmaster@subdomain.example.com
        </p>
        </li>
        <li>
        <p>
        postmaster@subdomain.example.com
        </p>
        </li>
        <li>
        <p>
        webmaster@subdomain.example.com
        </p>
        </li>
aws-java-sdk-acm/src/main/java/com/amazonaws/services/certificatemanager/model/ResendValidationEmailRequest.java