Twitter bootstrap – Datatables + JSON + best_in_place

I can not add gem best_in_place to my table.

class_datatable.rb:

  def data
    class.map do |record|
      [
        best_in_place(record, :name),
        best_in_place(record, :short_name)
      ]
    end
  end

There is an error: NoMethodError (undefined method `best_in_place’ for ClassDatatable:0xa9283a44)

My gem file:
source ‘https://rubygems.org‘

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.2.4'
# Use sqlite3 as the database for Active Record
gem 'ruby-oci8'
gem 'activerecord-oracle_enhanced-adapter'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 5.0'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .coffee assets and views
gem 'coffee-rails', '~> 4.1.0'
# See https://github.com/rails/execjs#readme for more supported runtimes
# gem 'therubyracer', platforms: :ruby

# Use jquery as the JavaScript library
gem 'jquery-rails'
gem 'jquery-turbolinks'
# Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
gem 'turbolinks'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.0'
# bundle exec rake doc:rails generates the API under doc/api.
gem 'sdoc', '~> 0.4.0', group: :doc

# Use ActiveModel has_secure_password
# gem 'bcrypt', '~> 3.1.7'

# Use Unicorn as the app server
# gem 'unicorn'

# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development

#---------------------------------My gems--------------------------------------------------------
#Twitter Bootstrap
gem "therubyracer"
gem "less-rails" #Sprockets (what Rails 3.1 uses for its asset pipeline) supports LESS
gem "twitter-bootstrap-rails"
gem 'client_side_validations'

#Datatables
gem 'jquery-datatables-rails', '~> 1.12.2'
gem 'font-awesome-rails'          # Icons 
gem 'foundation-rails'            # zurb foundation 

#Best in place
gem 'best_in_place'

#Russian langue
gem 'russian', '~> 0.6.0'

#Jquery UI
gem 'jquery-ui-rails'

#Paginate
gem 'will_paginate'

#-----------------------------------end---------------------------------------------------------
group :development, :test do
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug'
end

group :development do
  # Access an IRB console on exception pages or by using <%= console %> in views
  gem 'web-console', '~> 2.0'

  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'
end

Bundle install is done!

If I do like this on the page:

<% Class.all.each do |record| %>
  <%= best_in_place(record, :name) %>
<% end %>

That works.
However, the method does not work “def data”