old_contents: var classNames = require('classnames');
  var React = require('react');
  
  import StringUtil from '../utils/StringUtil';
  
  var FilterHeadline = React.createClass({
  
    displayName: 'FilterHeadline',
  
    propTypes: {
      onReset: React.PropTypes.func.isRequired,
      name: React.PropTypes.string.isRequired,
      currentLength: React.PropTypes.number.isRequired,
      totalLength: React.PropTypes.number.isRequired,
      inverseStyle: React.PropTypes.bool
    },
  
    getDefaultProps: function () {
      return {
        inverseStyle: false
      };
    },
  
    handleReset: function (e) {
      e.preventDefault();
      this.props.onReset();
    },
  
    render: function () {
      var filteredLength = this.props.currentLength;
      var totalLength = this.props.totalLength;
      let inverseStyle = this.props.inverseStyle;
      let name = StringUtil.pluralize(this.props.name, totalLength);
  
      var filteredClassSet = classNames({
        'h4': true,
        'inverse': inverseStyle,
        'hidden': filteredLength === totalLength
      });
  
      var unfilteredClassSet = classNames({
        'h4': true,
        'inverse': inverseStyle,
        'hidden': filteredLength !== totalLength
      });
  
      var anchorClassSet = classNames({
        'h4 clickable': true,
        'inverse': inverseStyle,
        'hidden': filteredLength === totalLength
      });
  
      let listClassSet = classNames({
        'list-unstyled list-inline': true,
        'inverse': inverseStyle
      });
  
      return (
        <ul className={listClassSet}>
          <li className={filteredClassSet}>
            Showing {filteredLength} of {totalLength} {name}
          </li>
          <li className={anchorClassSet} onClick={this.handleReset}>
            <a className="small">
              (Show all)
            </a>
          </li>
          <li className={unfilteredClassSet}>
            {totalLength} {name}
          </li>
        </ul>
      );
    }
  });
  
  module.exports = FilterHeadline;
  
new_contents: import React, {PropTypes} from 'react';
  import classNames from 'classnames';
  
  import StringUtil from '../utils/StringUtil';
  
  const METHODS_TO_BIND = [
    'handleReset'
  ];
  
  class FilterHeadline extends React.Component {
    constructor() {
      super();
  
      METHODS_TO_BIND.forEach((method) => {
        this[method] = this[method].bind(this);
      });
    }
  
    handleReset(e) {
      e.preventDefault();
      this.props.onReset();
    }
  
    render() {
      let {currentLength, inverseStyle, name, totalLength} = this.props;
      name = StringUtil.pluralize(name, totalLength);
  
      let filteredClassSet = classNames({
        'h4': true,
        'inverse': inverseStyle,
        'hidden': filteredLength === totalLength
      });
  
      let unfilteredClassSet = classNames({
        'h4': true,
        'inverse': inverseStyle,
        'hidden': filteredLength !== totalLength
      });
  
      let anchorClassSet = classNames({
        'h4 clickable': true,
        'inverse': inverseStyle,
        'hidden': filteredLength === totalLength
      });
  
      let listClassSet = classNames({
        'list-unstyled list-inline': true,
        'inverse': inverseStyle
      });
  
      return (
        <ul className={listClassSet}>
          <li className={filteredClassSet}>
            Showing {currentLength} of {totalLength} {name}
          </li>
          <li className={anchorClassSet} onClick={this.handleReset}>
            <a className="small">
              (Show all)
            </a>
          </li>
          <li className={unfilteredClassSet}>
            {totalLength} {name}
          </li>
        </ul>
      );
    }
  }
  
  FilterHeadline.defaultProps = {
    inverseStyle: false
  };
  
  FilterHeadline.propTypes = {
    currentLength: PropTypes.number.isRequired,
    inverseStyle: PropTypes.bool,
    name: PropTypes.string.isRequired,
    onReset: PropTypes.func.isRequired,
    totalLength: PropTypes.number.isRequired
  };
  
  module.exports = FilterHeadline;
  
subject: Bring FilterHeadline component to es6