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Errata for Using JRuby


The latest version of the book is P1.0, released almost 6 years ago. If you've bought a PDF of the book and would like to upgrade it to this version (for free), visit your home page.

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  • Typo
  • Tech. error
  • Suggestion
  • Maybe next edition
  • Not a problem
  • Reported in: B8.0 (14-Dec-10)
PDF page: 38

The last paragraph on page 38 has two sentences repeated at the top of page 39.

  • Reported in: P1.0 (06-Nov-11)
PDF page: 44

url.get_protocol # Isn't assigned.

url = 'http', '', '/titles' # FIFY--Johnneylee Jack Rollins

  • Reported in: P1.0 (06-Nov-11)
PDF page: 44
attributes.rb doesn't really make sense to have a code example for, seeing as it's purely for users to digest and not actually run.--Johnneylee Jack R...more...
  • Reported in: B8.0 (05-Jan-11)
PDF page: 58
Question I had reading this: does the become_java! method described earlier help at all with the "lost monkeypatches" problem? Or does it only apply ...more...
  • Reported in: P1.0 (26-Oct-11)
PDF page: 64
Issuing the command `ant`, the `do_compile` step fails due to not finding the jruby embed package. I have issued this before running `ant`, just to...more...
  • Reported in: P1.0 (06-Nov-11)
PDF page: 68
Referring to ruby methods as functions and then again as methods is somewhat confusing. I suggest referring to ruby methods as methods and java functi...more...
  • Reported in: P1.0 (17-Feb-11)
PDF page: 83

"and long-running programs well seem" should be "and long-running programs will seem"

--Romain Primet

  • Reported in: B8.0 (18-Jan-11)
PDF page: 106
There's a much better way to do platform detection for Jruby and regular ruby You can say: platforms :jruby do gem 'activerecord-jdbc-adapter'...more...
  • Reported in: B7.0 (27-Nov-10)
PDF page: 109
I think you are aware of an issue using JRuby 1.5.5 and Rails 3.0.3 but might make mention or make sure the reader is using newer version of JRuby (fr...more...
  • Reported in: P1.0 (15-Feb-11)
PDF page: 126
When generating the scaffold for Review, the first -- argument should be --migration, not --migrate. If using --migrate, the error at the command lin...more...
  • Reported in: P1.0 (16-Feb-11)
PDF page: 155
Building Ribs using the current version of rspec (2.5.0 as it type this), as installed by the previous commands, will fail as the Rakefile assumes the...more...
  • Reported in: B8.0 (13-Jan-11)
PDF page: 169
In the first ant example the name of the target ('hello_from_ant') does not correspond with the default target name ('hello'), so calling 'ant' withou...more...
  • Reported in: B8.0 (06-Jan-11)
PDF page: 226
I have had a great deal of trouble getting JTestR to work for my project. With the config from the book (0.6) I get: [INFO] Internal error in the ...more...
  • Reported in: B7.0 (01-Dec-10)
PDF page: 243
Last line "Next install the Monkeybars gem..." would read better if it were in a new paragraph. At the moment, this gives the impression it's a netbe...more...
  • Reported in: P1.0 (02-Jul-13)
PDF page: 250
Error installing monkeybars. Book says "jruby -S gem install monkeybars rawr" but neither is found in any repository. Installed rawr like this: jr...more...
  • Reported in: P1.0 (02-Jul-13)
PDF page: 261
Command to launch limelight demos does not work: book says "jruby -S limelight open" but I haven't been able to figure out what the correct command ...more...