1<!DOCTYPE html>
2<!--
3Copyright (c) 2013 The Chromium Authors. All rights reserved.
4Use of this source code is governed by a BSD-style license that can be
5found in the LICENSE file.
6-->
7<link rel="import" href="/tracing/base/base.html">
8<link rel="import" href="/tracing/importer/importer.html">
9
10<script>
11'use strict';
12
13/**
14 * @fileoverview Base class for trace data importers.
15 */
16tr.exportTo('tr.importer', function() {
17  /**
18   * Importer for empty strings and arrays.
19   * @constructor
20   */
21  function EmptyImporter(events) {
22    this.importPriority = 0;
23  };
24
25  EmptyImporter.canImport = function(eventData) {
26    if (eventData instanceof Array && eventData.length == 0)
27      return true;
28    if (typeof(eventData) === 'string' || eventData instanceof String) {
29      return eventData.length == 0;
30    }
31    return false;
32  };
33
34  EmptyImporter.prototype = {
35    __proto__: tr.importer.Importer.prototype,
36
37    get importerName() {
38      return 'EmptyImporter';
39    }
40  };
41
42  tr.importer.Importer.register(EmptyImporter);
43
44  return {
45    EmptyImporter: EmptyImporter
46  };
47});
48</script>
49