public void setTemplateVersion(String templateVersion) {
        this.templateVersion = templateVersion;
    }
<p>
The unique identifier for the version of the email template to use for the message. If specified, this value must
match the identifier for an existing template version. To retrieve a list of versions and version identifiers for
a template, use the <link linkend="templates-template-name-template-type-versions">Template Versions</link>
resource.
</p>
<p>
If you don't specify a value for this property, Amazon Pinpoint uses the <i>active version</i> of the template.
The <i>active version</i> is typically the version of a template that's been most recently reviewed and approved
for use, depending on your workflow. It isn't necessarily the latest version of a template.
</p>

@param templateVersion
       The unique identifier for the version of the email template to use for the message. If specified, this
       value must match the identifier for an existing template version. To retrieve a list of versions and
       version identifiers for a template, use the <link
       linkend="templates-template-name-template-type-versions">Template Versions</link> resource.</p>
       <p>
       If you don't specify a value for this property, Amazon Pinpoint uses the <i>active version</i> of the
       template. The <i>active version</i> is typically the version of a template that's been most recently
       reviewed and approved for use, depending on your workflow. It isn't necessarily the latest version of a
       template.
aws-java-sdk-pinpoint/src/main/java/com/amazonaws/services/pinpoint/model/EmailMessageActivity.java