private String authInformation() {
    if (authInformation == null) {
      StringBuilder stringBuilder = new StringBuilder();
      if (disableAuth) {
        stringBuilder.append("disable authentication");
      } else if (AUTH_METHOD_KERBEROS.equalsIgnoreCase(authMethod)) {
        stringBuilder.append(authMethod).append("(").append(krbPrincipal).append(")");
      } else if (AUTH_METHOD_SIMPLE.equalsIgnoreCase(authMethod)) {
        stringBuilder.append(authMethod).append("(").append(hadoopUsername).append(")");
      }
      authInformation = stringBuilder.toString();
    }
    return authInformation;
  }
Login with configured catalog user and create a proxy user ugi. Then the operations are
performed within the doAs method of this proxy user ugi.
amoro-common/src/main/java/org/apache/amoro/table/TableMetaStore.java