private String processStorageHandler(ASTNode node) throws SemanticException {
    if (node.getType() == HiveParser.StringLiteral) {
      // e.g. STORED BY 'org.apache.iceberg.mr.hive.HiveIcebergStorageHandler'
      try {
        return ensureClassExists(BaseSemanticAnalyzer.unescapeSQLString(node.getText()));
      } catch (SemanticException e) {
        throw createUnsupportedStorageHandlerTypeError(node, e);
      }
    }
    if (node.getType() == HiveParser.Identifier) {
      // e.g. STORED BY ICEBERG
      for (StorageHandlerTypes type : StorageHandlerTypes.NON_DEFAULT_TYPES) {
        if (type.name().equalsIgnoreCase(node.getText())) {
          Objects.requireNonNull(type.className());
          inputFormat = type.inputFormat();
          outputFormat = type.outputFormat();
          return ensureClassExists(BaseSemanticAnalyzer.unescapeSQLString(type.className()));
        }
      }
    }
    throw createUnsupportedStorageHandlerTypeError(node, null);
  }
Returns true if the passed token was a storage format token
and thus was processed accordingly.
ql/src/java/org/apache/hadoop/hive/ql/parse/StorageFormat.java