public String getPrincipal() {
        return this.principal;
    }
<p>
The Amazon Web Services service or identity that receives the permission. At this time, the only valid principal
is <code>acm.amazonaws.com</code>.
</p>

@return The Amazon Web Services service or identity that receives the permission. At this time, the only valid
        principal is <code>acm.amazonaws.com</code>.
aws-java-sdk-acmpca/src/main/java/com/amazonaws/services/acmpca/model/CreatePermissionRequest.java