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HackTheTower,Adopt Openjdk & Clojure workshop - December 2014 hack day is a hack day for any and all developers to come and collaborate on projects or discover new technologies together and enhance their skills.  Bring your laptop and your desire to learn & have fun!

This month I am also running an Introduction to Clojure workshop, to help you discover how simple, powerful and fun it is to do functional programming on the JVM.  Please add your name to the Clojure Workshop form if you want to attend or help out (or both)  

We are also co-hosting the Adopt Openjdk hackday

Come hack on the Java implementation that you use everyday!

* Improved OpenJDK test coverage 
* OpenJDK Warnings cleanup 
* Small Bugs Fixes 
* The betterrev project

If you're not familiar with the OpenJDK codebase there will be people there to help you get started, including some from IBM who work on OpenJDK professionally.

Rough Schedule 

You can get into the offices from around 9.30am onwards and have some breakfast and coffee, relax and take in the stunning view from the 26th & 27th floors of the Salesforce Tower (formerly known as the Heron Tower).

10.30am - Get together and discuss application ideas & things you want to try out. 
10.45am - Split into groups and get going 
1pm - Lunch time (sandwiches, quiche, fruit and drinks provided, requests taken) 
1.30pm onwards - Keep on hacking until you have had enough or want to go to the pub!

Sign up 
Please include your your full name so I can organise a visitor pass for Salesforce Tower, otherwise your entry to the event may be delayed.  Either update your name on your profile for this community or provide your full name when prompted during RSVP.

In total, there is space for around 150 developers on the day. Food & drink will be provided, thanks to our hosts Salesforce

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  • John S.

    Thanks to all at HackTheTower, especially those of you that helped me clean up afterwards.

    The Clojure workshop I am building is at - note this is still very much work in progress, but has a lot of references on the front page that you should find useful.

    1 · December 18, 2014

  • Chris K.

    Learnt a lot during Clojure meetup on Saturday. Lots of new avenues for investigation. Great to get v.good questions and answers from John and other members.

    Looking forward to next meetup :D

    December 14, 2014

  • Michael S.

    Awesome venue, people, view and great Clojure workshop run by John. This was a great and productive time, thanks everyone!

    1 · December 14, 2014

  • Mani

    There's a new initiative for everyone who wishes to checkout how Java libraries and F/OSS projects will work in JDK9, see Testing Java Early section in the Intermediate & Advance experiences document -­­­­­.

    1 · December 14, 2014

  • Mani

    Those having problems with building #OpenJDK on #Windows, try this one out -, if you haven't been through it before.

    1 · December 14, 2014

  • Julius G.

    Thanks to John for the place, view of london, and the food.

    Finally got to see the two SonarQube dashboards for OpenJDK8 and OpenJDK9.

    2 · December 13, 2014

  • Marius F.

    Awesome event. Will definitely be back.

    2 · December 13, 2014

  • Mani

    Thanks to all the devs in the OpenJDK group for the contributions made to the knowledge base - all poured back into the Getting Started Kit documents.

    You guys rock!

    2 · December 13, 2014

  • Eftar M.

    Hey guys, I'm stuck downstairs in the lobby waiting for someone to take me up.

    December 13, 2014

  • Marius F.

    I tried hard to follow the instructions to fetch a workable development environment for OpenJDK but without success. Installing SDK 7.1 Web fails on Windows 8, installing DirectX also fails on Windows 8, downloading the Ubuntu OVA file containing sources + Eclipse failed after getting 7.3 GB of content. I managed to get Babun, Hg and clone the whole dev repo, though - fine to read the sources but apparently not enough to actually build on Windows. I would be interested in learning from the experience of fellow developers who made the environment working.

    December 13, 2014

    • Mani

      Glad your download issues are resolved by using the VMs instead, now you can continue at home as well. And you have all the resources and help from us.

      December 13, 2014

    • Marius F.

      Yes, built jdk8 and in the process of building jdk9 right now. Quite cool the help I got was a great time saver.

      1 · December 13, 2014

  • Mani

    Hey guys, as a gesture of appreciation can I request you all to support this shout message, by retweeting it: or post messages in your own social media streams. Please do mention @HackTheTower @jr0cket @heroku @SalesforceDevs @salesforce in them.

    1 · December 13, 2014

  • David T.

    Hi Guys - Have to catch this next time. Sorry not to see inside the fabled tower!

    December 13, 2014

  • Edward Yue Shung W.

    Very sorry to cancel last minute, I've got to deal with a family issue. I'll contact the group separately regarding BetterRev :)

    December 13, 2014

  • Kotai V.

    Sorry for the late cancel, my cold has not improved at all and I'd rather not spread it around. See you at the next one. Have productive day!

    December 13, 2014

  • Nathan L.

    I'm relinquishing my spot to go to Tizen. I hope to see you at the Tower next month.

    December 12, 2014

  • shahin z.

    I wanted to attend this hack but the RSVP is closed, despite 10 available places. Is this an error ?

    December 8, 2014

    • Carl Matthew J.

      I have freed up a spot if that helps. I am at the Tizen Hackathon. The BeMyApp crowd were quite..persuasive...

      December 12, 2014

    • shahin z.

      Ok, thanks for letting me know John Stevenson.

      December 12, 2014

  • Dave F.

    Do we need to download anything in advance or will everything be provided on the day to get us up and running?

    December 12, 2014

  • John S.

    Please arrive by 10.30am latest on Saturday, otherwise you will experience a significant delay getting into the offices.

    If you did not supply a first name & last name, either on your profile or via the question asked, you will also experience a significant delay getting into the offices. Sorry, nothing I can do about this.

    December 12, 2014

  • Nawazish R.

    Sorry all, can't make this one.

    December 12, 2014

  • Raffaele L.

    Sorry, I had to cancel my RSVP, personal issues

    December 10, 2014

  • Mani

    *** My usual shout-out before we kick-off any Adopt OpenJDK hackdays! ***

    For those hacking away with the OpenJDK, as usual we have the beginners guide (Getting Started Kit -­­­­). Have a look at the new section 'Known issues' to address some recent issues. If you have a problem log it with us, if you have solved any such problems let us know so we can add it to this document.

    For the intermediate and advance folks, we have the (Intermediate & Advance experiences -­­­­). A number of new sections have been added from half-way through the document i.e. OpenJDK developers guide, list of JEPs, list of examples of tests, Visualisation of the OpenJDK codebase, OpenJDK9, etc... Plenty of hands-on exercises, before writing patches - see if any of the JEPs fancy your coding appetite.

    Come along with your laptops (VM Images: 10-12GB HDD space).

    Take aways: VM Images, documentation, experience and knowledge to work on OpenJDK on your own.

    November 24, 2014

    • Mani

      This familiar with OpenJDK can also join the Betterrev project at­

      November 24, 2014

    • Mani

      To you up your JavaEE, Arquilian, AngularJS, Javascript, etc... foo its a great project to contribute to.

      1 · November 24, 2014

  • John S.

    If anyone is interested in learning Clojure (or trying it out for a few hours), I am thinking of running a Clojure workshop at the December HackTheTower.

    Leave a comment here if you are interested (or want to help give the workshop).

    Thank you.

    November 12, 2014

    • John S.

      If you would like to join the Clojure workshop at HackTheTower in December, please add your name to this form so I know how big a room to organise

      November 24, 2014

    • John S.

      November 24, 2014

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