On Tuesday 24th April our colleagues at Docklands.LJC welcome Steve Wallin, Programme Director of IBM Runtime Technologies, who will be discussing Eclipse OpenJ9 – driving JVM innovation for Cloud Native Applications.

Steve Wallin profile

In anticipation of the event, we caught up with Steve for a quick-fire interview to get his thoughts on the session, the latest Java technologies and his advice for new programmers.

Why do you think this presentation is important for people?
JVM innovation is a hot topic right now! With Hotspot and Graal from Oracle, Falcon from Azul and now IBM open sourcing J9 at Eclipse there is real choice in finding the right JVM for your application requirements.

How do you ensure you are getting the most out of your hardware infrastructure and that your application is performing at its best?
There are a breadth of performance characteristics like application memory footprint, GC pause time, predictability/repeatability, ramp-up, peak throughput that all need to be carefully balanced by the JVM to provide the most efficient use of system resources. The whole model for the dynamics around these characteristics needs to change to include workloads designed for cloud and container deployment.

This talk will cover some of the new challenges which cloud and container scenarios create, what Eclipse OpenJ9 can already do to help and in which areas we are focused driving innovation going forward.

Would it be cool to reduce your memory footprint by 60% and improve startup by 40% simply by changing a couple of lines in your Dockerfile ?
Come and see the demo !

I’ll also make it interactive and you will get a chance to ask me anything you like.

What Java/JVM technologies are interesting you most at the moment?
It is great that there’s a renewed focus on language syntax , native interop and the removal of templating and generally minimizing the volume of code required for a developer to write to get the job done. Amber, Panama and Valhalla are all key projects at OpenJDK that will drive important features into the language over the next few years and will make the code easier to write, better to debug and enable cross language integration that JNI has not really been able to provide effectively.

In this session I will be focusing more on my interests in containerised applications, and how, with Docker kubernetes deployments we need to drive down the memory footprint and improve start-up performance to have Java competitive for microservices and cloud functions when compared to other technology options.

There are also broader challenges in the Java ecosystem for developers related to the new release cadence and migration challenges beyond Java 8. This tension between agility, time to value and stability are provoking some interesting discussions. I’m really pleased to have a team working with the LJC and a broad range of community members at AdoptOpenJDK (AdoptOpenJDK.net) which is helping to mitigate some of these challenges.

Finally do you have any advice for junior programmers entering the industry?
As a software developer and leader of software engineering teams for over 20 years there have been a huge number of ‘next big things’in the technology landscape where I have worked. As a junior developer understand your depth and breadth of skills and focus on finding your passion. If you are having fun and enjoying what you do then you’ll likely do your best work.

I do believe that the best programmers have an ability to keep up with the trends, but more importantly they understand how to use the softer skills to work with others, collaborate, lead, empathise with users and understand the motivations of those around them.
If you are able to continue to improve your personal, communication and presentation skills at the same pace as the technical skills then this puts you in a much better position to build better outcomes for your clients.

If you’d like to join us at the event, please register at: https://www.meetup.com/Londonjavacommunity/events/249668942/



On Tuesday 24th April we’re running an event in association with Microsoft: Live Coding with Spring Music. At the event we’ll be joined by Brian Benz, a Senior Cloud Developer Advocate at Microsoft. In his role, Brian helps Java developers to get the most out of Azure. Before joining Microsoft, Brian was a Solution Architect, Consultant, Developer, Author and Presenter at IBM and Deloitte amongst others.

Headshot 2015

In anticipation of the event, we caught up with Brian for a quick-fire interview to get his thoughts on the session, the latest Java technologies and his advice for new programmers.

Why do you think this presentation is important for people?

I’ll show people how to deploy and run Java applications in the cloud, using command line and open source tools you can get for free.  Free is good, and the cloud is powerful.  That’s a good combination!

Who do you think should come along?

Anyone interested in the latest tips, tricks and tools for Java developers.  And people who like swag, food and drinks, Microsoft and the LJC are buying!

What Java/JVM technologies are interesting you most at the moment? 

Cloud Native Java apps using Spring are most interesting to me these days.  Also, the related technologies that are interesting now, accessible by Java apps, like ML, AI, IoT, to expand the possibilities in today’s Java apps.

Any advice for junior programmers entering the industry?

You have it so good!  Cheapish hardware, meetups, stack overflow, cheap servers and services in the cloud.  Get started and find your way, the world is your command line.

The Live Coding with Spring Music session is happening at 18:15 on 24th April at Runway East Moorgate, 10 Finsbury Square, EC2A 1AF. If you’d like to join us, please register here:


You can also follow Brian on Twitter @bbenz.

Steve Poole

This is an interview with seasoned public speaker, IBM’s Steve Poole. Steve had a vision of creating a completely new kind of event as part of our Up Next initiative to mentor aspiring developers. The event titled “Find your Java voice” is happening in the evening of April 11th at IBM Southbank. You can RSVP here if you haven’t already: https://www.eventbrite.co.uk/e/find-your-java-voice-new-speaker-night-tickets-44485579566

We spoke to Steve and asked him questions about his vision for the event and why he feels getting involved in presenting is a great idea for developers.

Can you give us a tl;dr overview of the event and what is going to happen?

This event is designed to help give new speakers the chance to improve their presentation skills and gain a professional video of themselves speaking. We know how hard it can be for people to get a talk accepted at a conference. By having a video of themselves speaking it will help with conference selection committees who are looking for proof of presentation skills.

We’ll give every new speaker the chance to speak, be professionally filmed and receive feedback from our mentors. Since it doesn’t make sense to film the speaker before the advice we’ll give everyone the chance to speak first, get some feedback and then talk again later in the event where the will be filmed by IBM’s film crew.

Each new speaker has to come with a talk prepared. That’s not as scary as it sounds. We’re looking for a 5 minute talk (sometimes called a Lightning Talk) on any subject that has something to do with computers. No slides are needed (though not forbidden). Our main advice is to talk about what you know well. Whether it’s your experiences in installing Windows 10, what you think about <insert tech here>, how you wrote a really fast sort when you were 10 – The topic is not important. The important part is that it is a subject you know well.

The mentors will all be experienced speakers and will have many (and likely differing) opinions about speaking.

What are you hoping to achieve in this event?

That’s simple: help developers improve their career by gaining some vital speaking experience in a friendly but real life environment. I want our volunteer speakers to leave the event having had some fun, gained some useful advise and with a professionally produced video of them speaking.

Why do you think people should get involved as speakers?

Public speaking helps you with a few things. It certainly improves your confidence. Public speaking is often rated as a high stress activity but the reality is that it’s not actually that bad (trust me). People often think that they need to be the greatest ever expert on a topic before they could stand up and talk about it. That’s an incorrect view too. I would never claim to be ‘the’ expert. All my talks are through the lens of my experience. If I’m new to something I’ll share what I’ve learnt – as a newbie! So public speaking indirectly helps you throw off some of that ‘impostor syndrome’ that can hold you back.

Public speaking is generally good for your career. Personal visibility helps when looking for new opportunities and your talks will show others what you know.

Speaking also helps your communications skills across the board. The act of creating a presentation will teach you important aspects of presenting ideas and information to others. The confidence and personal insight you can get from speaking will helps you generally when dealing with other people in your life – whether difficult executives, or annoying cold callers, once you’ve spoken in front of an audience they will become easier to deal with.

Why do you think it’s important that junior speakers connect with mentors?

Having a mentor (at any stage of your life or career) helps you see things differently. It’s often easy to think you understand how the world works. With a single viewpoint you’re limited to using your single experience to predict and understand what you see. That can often lead to unfortunate under or over estimating the scale of new challenges. Having a mentor will help you get a different perspective and give you valuable insights. For this event I hope that the mentors present will help remove the mystique of public speaking and show that it’s not as scary as some believe.

Who would you recommend comes to the event?

We want three groups of people.

Firstly new (or nearly new) speakers. If you’ve willing to try standing in front of an audience for the first time or you’ve spoken at a conference once and want more help with your presentation skills this is the event for you.
Secondly we want seasoned mentors. You know who you are. Come along and pay forward the help that you got when learning how to be a public speaker.
Finally, and by no means last, we want an audience who will provide that realistic and positive experience for our new speakers.

Find your Java voice is happening in the evening of April 11th at IBM Southbank. You can RSVP here: https://www.eventbrite.co.uk/e/find-your-java-voice-new-speaker-night-tickets-44485579566 You can also follow Steve Poole on twitter: @spoole167


UP NEXT_idea

LJC JCP Committee Meeting 8th March 2018


  • Martijn Verburg
  • Sean Landsman
  • Sabrina Wons
  • Ilan Pillemer
  • Somay Nakhal
  • Abraham Marin-Perez
  • Ingo Hoffmann

Java EE -> Jakarta EE

Java EE has been donated to the Eclipse Foundation and reside as Eclipse EE4J projects, with the brand name of Jakarta EE.

The Committee discussed the pertinent founding documents:

Of particular interest was the Working Group charter where the new Guest Membership level (aimed at Java User Groups etc.) would give entities like the LJC a view into the Jakarta EE specification and steering groups, but would not give entities like the LJC a vote.

Action Item – Create a Poll

The Committee decided to poll the LJC membership and other important JCP / JSR related communities including (but not limited to):

  • LJC Membership
  • Global Java User Groups
  • London JBoss User Group
  • Java Champions
  • Java EE Guardians
  • EE4J Community

The poll will ask whether they still want the LJC to have a voting presence in the new Jakarta EE.  If so then the LJC can explore options to participate at that level, perhaps coming in as a Solutions Member.

Questions in the Poll

The London Java Community (LJC) and SouJava currently represent the global Java User Group community with regards to Java EE standards, i.e. technical review, legal review and voting on whether standards should progress.

With Java EE moving to the Eclipse Foundation (as Jakarta EE), a new Working Group with specification / steering committees governing the future of this technology has been formed.  The LJC would like to understand if Java User Group members) around Java EE technology is still interested in us representing them at Eclipse. So here are some questions!

  1. Do you directly or indirectly develop with or use Java EE technology?
    (if you use Spring, then this is a Yes).
  2. Are you aware that Java EE has moved to the Eclipse Foundation as Jakarta EE?

Please read the following documents before answering the next questions:

  1. Would you like the LJC to have voting status at Eclipse for Jakarta EE?
    1. Yes
    2. No
    3. I don’t know – it’s too complicated to figure out
    4. I don’t know – I didn’t read the docs I was asked to 🙂

  2. Please leave any further comments

OpenJDK / Java SE

The Committee discussed the pertinent founding documents:

Action Item – Continue Discussing JEP12

A longer discussion on the drawbacks vs benefits of JEP12 is required, including:

  • Impact on independent implementers of Java (e.g Azul, IBM etc).
  • Impact on tooling vendors (e.g App Dynamics, Jetbrains etc).
  • Impact on libraries (e.g ByteBuddy, Spring etc).

Action Item – Test Drive Java 10

Martijn encouraged members to try Java 10 out early and give feedback.  We’ll also encourage the LJC at large to do this.

Action Item – 6 month release cycles and support

The committee discussed the concerns around the 6 month release cycle and the lack of Oracle’s LTS support for OpenJDK.

Other vendors and/or the community could of course support OpenJDK (and variants / versions of it), but that support is likely to be seen as fragmented by the ecosystem.

Adopt OpenJDK Build Farm

Martijn introduced the Adopt OpenJDK Build farm, the new place where the OpenJDK community (including several LJC members) are collaborating on a new build farm for Java to be shared and used by the community at large:


We voted “Yes” for the re-submission of this specification within.  Jigsaw and Java 9 will represent a solid foundation for a new evolution of the Java platform, one that is nimbler, more lightweight and more secure.  Is this work complete?  No, there are still outstanding issues and feature requests to go, especially as the ecosystem learns to use the new modulepath and friends.  But the basis is sound and we think a large minority will take up the new module system once Java 9 goes GA.

The results of the vote on the reconsideration ballot (Public Review) for this JSR are here: https://jcp.org/en/jsr/results?id=6016

We voted no the first time around because we wanted to see final consensus on the last few outstanding issues as well as some bedding in time of recent, far-reaching consensus decisions.

Our official comment

The LJC votes yes and echos IBM’s thanks to Oracle (as the specification leader) and those in the JSR 376 Expert Group who dedicated their time to reworking and clarifying areas of the specification that we were concerned about.

The LJCs concerns (https://londonjavacommunity.wordpress.com/2017/05/09/explanation-of-our-no-vote-on-jsr-376-java-platform-module-system/) over interoperability with the Java ecosystems defacto build tool / module repository (Apache Maven) have been addressed as have the concerns over the ability for independent implementations of the compiler to be built (noticeably ejc).

The disposition of outstanding issues as agreed amongst the Expert Group was handled really well and it was heartening to see the evident collaboration as described in the detailed minutes of the EG’s meetings in the past month.

We see this release of JPMS as the strong foundation for a new Java SE platform architecture, and expect to build upon this with feedback and experience from Java User Group members.

Further Notes

The specific technical details of what was agreed and what was deferred are in the minutes:

Some highlights include:

  • Agreement on version name format(s).
  • Agreement on rules around Automatic Module Naming and a guide on how to best use those (important for the Maven ecosystem).
  • Dealing with multiple versions of the same module was deferred.
  • Agreement on relaxing Strong encapsulation as a default (means fewer apps will break out of the box, but get a warning instead).
  • Tidying up on some keyword usage (allowing the Eclipse compiler to be built).

We think the Spec lead and EG did a great job in coming together to resolve the outstanding concerns and hope that this can be a model for further collaboration over particularly far-reaching / complex part of the Java ecosystem development going forwards.

Martijn (on behalf of the LJC JCP Committee, on behalf of the LJC)


We voted No because we want to see final consensus on the last few outstanding issues as well as some bedding in time of recent, far-reaching consensus decisions.  No we don’t think this should or will delay Java 9 significantly, we expect a re-submission and eventual “Yes” vote to this specification within 30 days, please see the JCP Process Document for how this works.  No, we don’t think JPMS/Jigsaw is fundamentally flawed.  Yes we want extra time and thought going into JPMS by the wider ecosystem (and its authors) as this new module system will impact Java far more than the move to generics in Java 5.

The results of the vote on the Public Review for this JSR are here: https://jcp.org/en/jsr/results?id=5959

Our official comment

We echo SAP’s comments in that we absolutely recognize the tremendous achievements and the great work that has been carried out until now by the EG members as well as (and especially) by the Spec Lead himself.

The LJC is voting “No” on the spec *as it was submitted* at the start of the voting period. During the 14 day voting period, great progress was made by the Spec Lead and the EG to reach consensus on some very difficult issues such as #AutomaticModuleNames. However, there are still on going conversations on some of those issues and there simply has not been enough time spent by the ecosystem to discuss some of the new designs in enough depth or enough time spent implementing and testing prototypes based on the latest spec, e.g. The Eclipse ejc compiler or the latest Automatic Module Naming design in Maven.

If required, we very much look forward to being able to vote ‘YES’ in <= 30 days on a version that has had that little bit of extra time for the EG (and the ecosystem) to discuss / implement / test some of these difficult spec items. Certainly the last 14 days have shown that consensus can be reached even when viewpoints have started in opposing corners, and we think another short time period to really bed in the last sticking points is needed.

Further Notes

We voted “No” based on careful technical analysis of JPMS, the RI (Jigsaw), comments on the mailing list as well as out in other public forums.  We then put the existing specification to the test on a Java 9 hackday along with the Virtual JUG and ~15 JUGs worldwide.  The conclusion was that JPMS still has some outstanding issues to be resolved or issues that (despite having recent resolutions), were still not bedded in the minds and/or prototypes of the larger ecosystem.

For our membership, interoperability with the Maven build ecosystem and the ability to build an alternative compiler implementation (i.e. Eclipse’s ejc compiler) is paramount.  Although consensus is rapidly forming around those two items, our membership felt that they needed some extra time before they felt comfortable with voting “Yes”.

This is what the JCP is for (no, not just politics)

Casual observers and some parts of the tech media will likely come to the conclusion that this is all just about big company politics. Recent public blog posts and open letters will have fuelled that sentiment, but we urge people to read the comments accompanying “No” votes.

Although Oracle are the stewards of Java, the JCP Executive Committee (EC) is meant to act as guide for the Java ecosystem as a whole and we feel strongly that it is working as intended in this case.

What next?

The Spec Lead (Mark Reinhold) has publicly stated that if it needs more time, then it will get more time, so we expect to see a revised spec within the 30 days and expect to vote “Yes” in good conscience and not delay Java 9 (the spec).
Martijn’s Personal View 
There was a lot deep dive technical analysis and tough discussion in the past two weeks with a lot of smart, passionate technologist’s who all love Java.  This cannot be a bad thing :-).  That said, I’m tired and will now have a sleep before Devoxx UK!
Martijn (on behalf of the LJC JCP Committee, on behalf of the LJC)

Attendeed: Martijn Verburg, Sean Landsman, Ingo Hoffmann, Omar Bashir

  • Welcomed Omar as a new member!
  • Discussed JSR 363 – Units and Measures. Omar pointed out that it looked good overall but he had some concerns about the verbosity / boilerplate nature of having to use Factories and Builders in order to get going. He noted that the Java 6 compatibility made sense (IoT, Android and other older platforms). Martijn commented that DI of some sort might help tackle the verbosity, but that the Spec Lead and EG had likely discounted that in order to allow it to be used across a wider set of projects.  Omar will send in final feedback by Sunday the 7th.
  • Discussed the vote for JSR 380 – Bean Validation 2.0.  Unanimous yrs, Ingo noted it was early stages and that we should have a more careful review when there was the beginnings of a RI.
  • Discussed the vote for JSR 367 – JSONB – Group looked at outstanding issues and send a message to the Spec Lead over a concern that JSONPointer support had not been addressed.  Will wait until Sunday evening (7th) before casting final vote.
  • Discussed nominations for JCP awards. Unit of Measure and Jigsaw seemed to be the outstanding JSRs, more research required on the Adopt a JSR award.
  • Martijn will give feedback at the next meeting about the Aug 7th EC phone conference, covering Java EE 8 as Oracle sees it.


Martijn (on behalf of the LJC JCP Committee)

Attendeed: Martijn Verburg, Sean Landsman, Ingo Hoffmann, Abraham Marin-Perez

  • Welcomed Abraham and Ingo as new members!
  • Discussed MicroProfile.io and status of JavaEE 8 – the LJC will officially support MicroProfile and run hackdays against vendor implementations of the profile.  The LJC is waiting until JavaOne in Sept to see what is happening with Java EE 8 but hopes that Oracle will join the collaborative MicroProfile effort.
  • Discussed JSRs under review and agreed to go away and do more research and send feedback to the list:JSR 380 – Bean Validation 2.0 – JSR Review
    Appears on the ballot: 26 July 2016
    URL for proposal:
    https://jcp.org/en/jsr/detail?id=308JSR 362 – Portlet Specification 3.0 – Early Draft Review 2
    Last day of review: 12 September 2016
    URL for EDR 2 materials:

    JSR 367 – Java API for JSON Binding – Public Review
    Appears on the ballot: 26 July 2016
    URL for Public Review materials:

    JSR 363 – Units of Measurement API – Proposed Final Draft
    URL for PFD materials:

  • Discussed an IP and copyright of APIs proposal that was put to the EC.  Decided that further in depth study was required before commenting.
  • Martijn will arrange the next meeting before the Aug 7th EC phone conference


Martijn (on behalf of the LJC JCP Committee)

TLDR: Go to microprofile.io and join the mailing list there and fill out the survey!

Recently the LJC officially put its support behind MicroProfile, a new open source project and collaborration between Java EE vendors and the developer community to provide enterprise developers comfortable with Java EE a way to move into the microservices space.  The LJC will host hackdays as Microprofile gets closer to its first GA release in September 2016.

The recent interview with JAX Enter sums up the current state nicely, so I’ve repeated it here verbatim.

JAXenter: Red Hat, IBM, Tomitribe, Payara and the London Java Community joined forces to create MicroProfile. What are the objectives of this initiative?

Martijn Verburg: The initial goal is to provide developers who are most comfortable with enterprise Java (Java EE if you will) a starting point to work with microservices in a non vendor specific way (which is what they’re used to from the Java EE world).  The aim is then for the developer community to actually drive what they feel they need in microservices runtime/API, so instead of the vendors ‘guessing’ that you might want security, or logging or discovery or whatever. It’ll be up to the MicroProfile community to help define what should go in and what should stay out.

Some open standards will likely fall out of this to give businesses confidence about the longevity and the vendor neutrality, which is something they’ve enjoyed and trusted from the Java EE ecosystem.

JAXenter: What is the London Java Community’s take on the current state of Java EE? How can MicroProfile bring it forward?

Martijn Verburg: Java EE has clearly stalled with the lack of progress on Java EE 8. Although many of us feel that the time for the monolithic Java EE platform standard is possibly over, there’s still enormous value in having standards around key pieces of Java Enterprise technology. Enterprise Java does after all still drive billions of dollars worth of IT business and directly or indirectly drives trillions of dollars in the global economy.

JAXenter: How is the goal of MicroProfile different from Java EE Guardians’? What is the London Java Community’s contribution to this new initiative?

Martijn Verburg: The goal of MicroProfile is to bring collaboration around microservices for enterprise Java developers.  This is very separate to the Guardians group, who are advocating Oracle to put resources back into the Java EE 8 platform.

JAXenter: How can MicroProfile push forward microservice innovation in Enterprise Java?

Martijn Verburg: By asking the community what they want and releasing early and often.  Then standardizing on what the community and the vendors feel are the right APIs that need longevity.

JAXenter: Do you hope to generate a reaction from Oracle?

Martijn Verburg: We hope they join in the initiative!  Oracle has shown that it can lead in open source via OpenJDK and we know that like all vendors, they have an interest in microservices.  Some common ground between all of the vendors and the community will help ensure that enterprise Java is well placed for the challenges going forwards.

JAXenter: How can the community participate in the MicroProfile effort?

Martijn Verburg: By going to microprofile.io and joining the mailing list there, filling out the survey and shortly contributing code!

Hi all,

We’ve been remiss in posting our thoughts on our official votes for various Java standards that go through the  Java Community Process (JCP) Executive Committee (EC). So in order to get back into the swing of things we thought we’d start with the all important Java 9 SE vote!

For JSR 379 – Java SE 9 (See full results from all voters) we voted Yes for the JSR Review Ballot with the following comment:

We are very happy with the technical content and have high hopes that it will increase the longevity of Java in the age of containers and smaller devices.

We are disappointed with the relatively late release of this JSR. Since much of the RI and TCK has already been built, it makes it much harder for independent implementations to reach the market in a timely manner.

We see that Red Hat, IBM, Google and Oracle will likely make up the EG and we hope to also see wider participation from other JVM vendors.

In terms of technical merit we’re broadly happy.  There are certainly issues with Jigsaw vs the ‘real world’, which was anticipated and hopefully will be mitigated by further early testing of JAva 9 and some compromises made by both the authors of libraries, frameworks and products and the authors of the Jigsaw module system.  The rest of Java 9 offers up loads of exciting new features including HTTP 2 support, JShell and a host more.

To add some further insight on the other half of our comment, we need to explain the current challenge we have with OpenJDK vs the JCP standardardization process.  In short, OpenJDK is the GPLv2 licensed open source project that is the Reference Implementation (RI) for Java SE.  Oracle and most (not quite all) other vendors create their commercial ‘Java’ releases from OpenJDK.

However, in order to release a ‘Java’ which can be called Java, you must pass the Technical Compatibility Kit (TCK) which is produced as part of the Java Specification Request (JSR). If the JSR is delivered late on in the development of OpenJDK it puts vendors who produce a non OpenJDK based implementation at a massive disadvantage and even puts the vast majority basing their implementations off OpenJDK at a disadvantage in terms of getting their product complaint and to the market.

There’s also no real mechanism for the community to push back against proposed changes via the JCP, as so much work has already been done in OpenJDK. That is, what’s in OpenJDK is effectively fait accompli.  That’s not necessarily a bad thing as OpenJDK generally speaking provides that highly collaborative open source environment which allows for plenty of community feedback and influence (it’s still nominally Oracle controlled, but it’s about as good as you can get given single vendor ownership).

It does place OpenJDK and the JCP at odds though and we look forward to working with Oracle and the JCP to resolve that (there are some early proposals being discussed).


Martijn (On behalf of the LJC JCP Committee)

What is the LJC

The London Java Community (LJC) is a group of Java Enthusiasts who are interested in benefiting from shared knowledge in the industry. Through our forum and regular meetings you can keep in touch with the latest industry developments, learn new Java (& other JVM) technologies, meet other developers, discuss technical/non technical issues and network further throughout the Java Community.