<!DOCTYPE html>
<!--
Copyright (c) 2013 The Chromium Authors. All rights reserved.
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->
<link rel="import" href="/tracing/base/base.html">
<link rel="import" href="/tracing/importer/importer.html">

<script>
'use strict';

/**
 * @fileoverview Base class for trace data importers.
 */
tr.exportTo('tr.importer', function() {
  /**
   * Importer for empty strings and arrays.
   * @constructor
   */
  function EmptyImporter(events) {
    this.importPriority = 0;
  };

  EmptyImporter.canImport = function(eventData) {
    if (eventData instanceof Array && eventData.length == 0)
      return true;
    if (typeof(eventData) === 'string' || eventData instanceof String) {
      return eventData.length == 0;
    }
    return false;
  };

  EmptyImporter.prototype = {
    __proto__: tr.importer.Importer.prototype
  };

  tr.importer.Importer.register(EmptyImporter);

  return {
    EmptyImporter: EmptyImporter
  };
});
</script>