public String getPrincipalName() {
    return principalName;
  }
Gets the constructed principal name for this DeconstructedPrincipal
<p/>
The principal name is the combination of the primary and instance components:
<ul>
<li>primary/instance</li>
<li>primary</li>
</ul>

@return a String containing the "realm" component of this DeconstructedPrincipal
ambari-server/src/main/java/org/apache/ambari/server/serveraction/kerberos/DeconstructedPrincipal.java