@RequiresSession
  public KerberosPrincipalEntity find(String principalName) {
    return entityManagerProvider.get().find(KerberosPrincipalEntity.class, principalName);
  }
Find a KerberosPrincipalEntity with the given principal name.

@param principalName name of kerberos principal to find
@return a matching KerberosPrincipalEntity or null
ambari-server/src/main/java/org/apache/ambari/server/orm/dao/KerberosPrincipalDAO.java