KerberosToken getKerberosToken(String username, String keytab) {
    try {
      return new KerberosToken(username, new File(keytab), true);
    } catch (IOException e) {
      throw new IllegalArgumentException("Failed to instantiate KerberosToken.", e);
    }
  }
Instantiate a KerberosToken in a backwards compatible manner.
@param username Kerberos principal
@param keytab Keytab on local filesystem
accumulo-handler/src/java/org/apache/hadoop/hive/accumulo/AccumuloConnectionParameters.java