Live Coding on Java 8 Date Time API

Yesterday I recorded a live coding session on java.time. Below is all the information so you can code along if you like:

The Video

The Source Code

All the source code is freely available on github you can get this running the following command:

The (brief) details for setting up the IDE can be found in the readme.

The Slides

Introduction to Java 8 java.time from Jim Gough

User Group Visit to San Francisco

Why am I in San Francisco? 

Is it:

• A micro brewery pub crawl?
• The fact it's almost 20°C tomorrow?
• To attend a Brazilian BBQ in January? 

These things are certainly going to be a nice bonus of being here, however that's not the main reason. I'm here representing the London Java Community at Oracle's big annual user group leaders convention. The purpose of the conference is to bring leaders of a variety of different Oracle user groups together to discuss best practices and drive improvement of communities and involvement for all those concerned. Particularly this year the topics I am interested in and will be participating in are:

• Using social media - I'm particularly interested in discussing handling negative discussion and feedback via this extremely public forum.
• Turning members into leaders and growing speaker talent. This has been an active stream in the LJC and Trisha Gee and team have been doing a fantastic job of running workshop and helping people gain the courage to make that first talk. 
• Gamifiying your user group experience and improving user group content. I'm mainly interested in this because I get motivated by badges and awards for certain things. I think it could put a fun spin on how we run certain events in the LJC.

I plan to blog about interesting conversations and what comes out of these themes over the course of the week. The summit will only be the beginning of the discussions and I look forward to seeing more about what our members think to some of the ideas and which may work for us. 

When discussing any kind of conference and benefits of conferences I always say that it doesn't have to be a specific talk that motivates you but a catalyst to change. All the major turning points in my career have been down to ideas gained at conferences. It will be interesting to be involved in a non technical conference across a range of different products, experiences and backgrounds. 

I have very kindly had partial sponsorship from the LJC and the JCP Program Office to be here this week and I can't thank them both enough for the opportunity. 

I am now a JCP Executive Committee Representative

Why are the JCP helping to sponsor my visit here? After 3 years of working on JSRs with the London Java Community with the LJC JCP committee I have now stepped up my involvement and represent the LJC directly with other JCP executive committee members. I am attending my first face-to-face meeting at the end of this week. I'm really thrilled to be working with so many fantastic organisations and individuals to help maintain and form standards within Java. As the meeting has official minutes it's unlikely I will post anything further. 

Contributing to Java

I have just written a post on contributing to Java for the London Java Community's JCP Panel. You can find the full post here:

Contributing to Java: The JSPA and the OCA

The LJC Open Conference 2013

Yesterday I attended my 5th LJC open conference, and as always it is one of my favourite times in the year. Most of the major conferences have been and gone and people are winding down ready for Christmas. However, the combined knowledge and enthusiasm of the community doesn’t reflect this slower time of year. 

This year I got a lot more involved with helping in set up and planning board activities, as well as giving a talk on TDD primer. The session board looked like this first thing in the morning:

There are roughly 5 streams of topics at the conference, what interested me was the focus on development of people skills and testing of code - there was definitely a strong feel of craftsmanship in the air. 

• Core Java
• Java EE/Application Servers
• Testing tools and processes
• Community and soft-skills
• Workshops

The slides I gave for my talk are below, it's based on a longer talk I gave at JAX London. The idea was to give people who haven't tried Test Driven Development before some guidance in getting started and what some of the pitfalls can be. Sadly I had a Mavericks and projector based issue, which meant I lost about 10 minutes of the talk. However, the show must go on so I covered the first slides without a project whilst the hero of the day John Stevenson fixed the projector. Minstrels will write songs about this day...

Test Driven Development Primer LJC Open Conference from jpgough

I got some good feedback on the talk - I need to refactor the examples in the slides a fair bit, this will be done when I put the information I presented at JAX into a blog series.

I also went to a talk on testing with Spock. It's not usually something I'd be particularly interested with it not being core Java, however it was interesting to see a different take on testing. I quite liked the way you can be verbose in your tests and get a lot of boilerplate you require in JUnit for free. The final talk I went to was on progressing your career without losing technical focus. A lot of people looking for mentorship and guidance at a senior level on how to remain technical. It was a good session, but only touched on a few issues in the time - it looks like something that could be run as a bigger round table.

It was great to catch up with old friends and people I've worked with in the community over the years, especially now I am not in London as often. It's also helped me start to focus on my own learning plan for next year. It's always a motivating weekend and if you didn't get chance to go this year I can't recommend it enough. As always thanks to the sponsors IBM for a great venue and beer from Zero Turnaround and some dodgy car salesman Simon Maple for organising the event.

Leaving London and keeping in touch

At the beginning of the beginning of the year Megan and I had our first child Emily and moved to Bedford. This sounds more severe than it actually was, the commute down from Bedford to Kings Cross is only around 40 minutes. It's been a busy 6 months since then working on multiple projects with Stackthread, getting promoted to Vice President at the firm and as you can imagine not too much sleep.

As a family, we have decided to take a step which will involve us spending a lot more time together - but sadly means that I will be leaving London as a work hub. Having just completed major project milestones at the bank I work for, I decided it was time for a change of roles and found an exciting opportunity in Milton Keynes. From a personal perspective this also cuts down a 2 hour commute (each way to Canary Wharf) to 20 minutes, and reduces my outgoing costs on expensive rail tickets.

This has left me with many decisions to make about what projects to keep working on in London and how to keep in touch with specifically the London Java Community and the London Java Community Process Committee. For now, I'm not going to make any rash decisions and see how things pan out in terms of time available and what I realistically commit to. With ever limited time, I am trying not to spread my contributions too thinly and want to ensure that whatever I do chose to work on in the next few years has a solid impact.

Currently, I next plan to be in London on:

• 29th-30th October for JAX London.
• One Saturday towards the end of November for the LJC Open Conference

JAX London 2013 - TDD: The Benefits are more than just the tests

An introduction to my talk at JAX 2013 - also published here.

Back when I first started my career as a developer following University I was unleashed with little training in best practices, development methodologies or what to expect from the uncertainties in real world development. Before I could start to learn all these things I was quickly placed in my first job. The type of role I was placed into was fix problems and develop new features - with only guidance relating to the specific tasks at hand. There was no training on industry best practices, which underpin the quality of the software as professionals we strive to deliver - my own development languished.

Several years on, in my own time and through quizzing various industry leading technologists like Sandro Mancuso (at JAX London 2012) and Martijn Verburg (at numerous beverage centric establishments) I started to discover my personal points of improvement. I realised that there were steps I could take to improve the approaches I had in my toolbox for software problems. I took a look at my peers and people that were applying for job roles. Many listed Test Drive Development (TDD) as something that they used on a regular basis. I very quickly realised that a lot of people claim to practice TDD, but either don't do this at all or write integration tests rather than unit tests, as well as other ideas about what TDD is.

My talk at JAX London 2013 is designed for developers who have been too busy to appreciate the less obvious benefits of TDD, particularly the side effects and task breakdown from a cognitive perspective. The session will cover the basics of TDD, the use of mocking and how this helps break up the coding complexity using code and architecture examples. I will also convey my own experience of converting to TDD along with the benefits I have realised and how to convince developers who don't want to test the approach has merits outside of just high test coverage. The talk does not aim to sell TDD, but instead present facts and experiences that I have gained over the last year so developers can form their own opinions.

From taking these steps myself I produce code closer to the requirements, more maintainable code that is able to respond quickly to changes and my colleagues can look at the code and tests and quickly understand what is going on. Conferences are often the catalyst for personal improvement, and people interested in this space but haven't had time to explore it themselves will get some good practical advice on how to get going and what to expect.

Highlights From Java One 2012

Highlights From Java One 2012

When my talks were first accepted for Java One 2012, I never imagined I would feel like this at the end of the week. Currently, I'm a mixture of so burnt out I can barely walk yet so full of adrenaline I don't want to sleep. As a technologist this week has been the highlight of my career. This post will detail a few of the highlights of the week for me.

Keynote and Lunch with James Gosling

If someone had told me I'd be sat having lunch with James Gosling after participating in the Java One community keynote I would have branded them insane. However, that's exactly what happened today. With my friends in the London Java Community we had a panel session discussing a flag ship initiative we have been working on known as Adopt-a-JSR. The keynote was so far from corporate it was refreshing, it was all about community for the community. 

We saw key technical companies participate in the initial panel, us and then a crazy robot chasing down Oracle executive Georges Saab on stage. Then something special happened, James Gosling entered the stage. He was talking about his new development at Liquid Robotics. The best part about his appearance was James was back amongst a community of developers that have a high degree of respect for him and his work with Java. I found his presentation a highlight of innovation that is ongoing in the industry. After the keynote I headed over to Stephen Chin's Java Desktop lunch. We were sat at the same table as James and discussed details of the UI that he had built and demonstrated during the keynote and discussed some of the problems that data heavy systems would cause web based applications. What a great note to end Java One on.

Java FX

Java FX has been technically the most exciting product of Java One for me. It really starts to represent the revival of Java on the desktop. Although Swing has lived on over the last few years, how many people have really wanted to do this? Java FX simplifies a developer's ability to rapidly create flexible and maintainable user interfaces. Scene Builder also provides an abstraction away from code, so you can now have a design team that builds the basic CSS and component layout and the development team adds the functionality on top. 

At Java One myself and Ben Evans presented our toy project visualising garbage collection in Java FX.   One other highlight of the week was when I met Jim Weaver near the exhibition hall. He asked me if I'd like to come over to watch him give a demo. Within about 15 minutes I was stood at the front of the demo grounds giving a presentation on I'm new to Java FX and this is what I've built. Thanks Jim! That said it was great fun and all the Java FX team are really fun people to hang around with. 

My challenge for our next JUG meeting is to get a Java FX example running on the Raspberry Pi. Hopefully the Pi will arrive before then, if not I'm really looking forward to sharing everything else about Java FX back in the London Java Community.

Adopt a JSR

Adopt-a-JSR is a global initiative that was kicked off in London to help make the JCP (Java Community Process) relevant to Java developers and increase their participation. Adaptavist's Dan Hardiker had the following to say about the project:

Jax - What in the development world (project or otherwise) is really interesting you at the moment?

Dan - The Adopt-a-JSR programme ran by our own LJC, is one of the most important initiatives I've seen in a long time. It puts developers back in the driving seats helping to steer decisions on important areas of the language they live and breathe.

From attending Java One it was clear to see that although we have managed to reach senior members of the community there are still many members of the Java community that are not aware of the program or the aims. A second interesting point was that many of the developers attending our sessions are not members of Java User Groups. In order to address these points we are going to look at how we can be wider reaching to developers that are not members of JUGs. Recording sessions and broadcasting them to the wider community is going to be part of the strategy we look at to address this.

JSR-310 - New Date Time API

In the background to Java One we have been working hard with Oracle and Stephen Colebourne to address the final design decision of JSR-310. A lot of hard work is going into this JSR behind the scenes and at the end of some fairly heated debates we are looking to be on track for Java 8. If you're reading this and you still want to help, we are making a push for people to help us with the following:

In our continued efforts to evaluate and improve the Threeten Date/Time API for Java 8 we were discussing the effort of porting code from existing APIs. Does anyone have open source examples of code which they wrote against the existing java.util.Date or Calendar that you felt was overly complicated? I have some code myself, but I'd really like to hear from you if you have stuff that's open source and available for hacking on.

If you can help please feel free to drop me a tweet @JavaJimLondon.

Embedded

One final point that really excites me is robots! There has been a taster of Java running on embedded hardware, we've also seen some really cool demonstrations of Java FX running on embedded hardware and a Raspberry Pi. This is what I'm going to be playing with over the next few months, along with Java FX to try push the bounds of what is possible.

Thanks

A big thanks has to go out to Sharat for organising a fantastic Java One, this year really had a community feel about it. Thanks to all the speakers and the content committee, it's been awesome!

Highlights From Java One: Day 1

Java One - San Francisco

Today was my first day at Java One, and my first international conference. It has been an immensely fun day with loads going on.

8.15 AM - First talk of the conference - ours!

The first session we attended was our talk titled "The bluffers guide to terminology". The talk walked through terminology that complicates our industry, and made observations on how business, technical and academic domains are complicated enough without additional terminology. We walked through the different sections explaining terms and simplifying them so everyone could understand. For 8.15am the audience were very engaged, and it was clear that this was something everyone could relate to. We concluded that you have to be very careful when picking terms to represent your domain model objects in software development. You need to think about having a suitable abstraction that is clear as to what it represents in the domain, but doesn't complicate the domain further.

Winning an award

For the last 18 months, myself and colleagues from the London Java Community have been working on two key initiatives - Adopt a JSR and Adopt Open JDK. Today we were awarded with a Duke's Choice Award for the hard work we have put in inspire the community to be more involved in contributing to the future of Java. It was very exciting to see the LJC's name on the big screens at the Java One keynotes. Although winning an award was not something we set out to achieve, it is an honor. It has inspired me to carry on pushing on the initiatives we started and to use Java One as an opportunity to encourage global participation. It's also got me thinking about a future initiative, but for now that will remain top secret.

Technical Keynote

I'm still processing some of what was in the keynote, but my initial reaction is how excited I am about Java on the desktop. Having experienced the pain of Swing and context switching between .Net and Flex as alternatives, I can really see a future for Java on the desktop. That wasn't all however, we actually got to see Java FX running on a Raspberry Pi and other embedded devices. There's actually an embedded version of the Java One conference scheduler deployed around the hotels! This has really steered my interest for the conference as I'll be looking to attend a large number of Java FX talks this week at Java One. We also have our talk on visualising the Java GC model on Tuesday, which will go into building an application from the beginning in Java FX what we have learnt about the technology and how to use Java FX as a teaching and visualising technology from a slightly different perpective to grids and graphs.

Party

The day ended with collecting the Duke's Choice Award and a party in the street next to the hotel. Most of us have now returned to try and shake the jet lag before a packed day tomorrow.

FrAgile Development

On June 12th I gave a lightning talk on FrAgile Development at Skills Matter in London, you can watch the video here. It was by far the most controversial talk I have given to date. Before I instantly get flamed by Agile fans the talk was not to criticise the methodology, but was a play on words and/or what can start to happen if things go wrong. The best part about the talk was the range of reactions that the audience took from the talk, which I will summarise at the end.

For the purpose of this post the FrAgile Developer writes in red, the voice of some reason will be in blue. Imagine them as an angel and a devil sat on the developers shoulder.

The slides went through some bad practices that I've seen (and participated in whilst learning and not knowing any better). During research it seems others have also thought of Fragile development as a concept and c2.com was a great reference point.

Ctrl CV Design Pattern

Refactoring is expensive, and copy paste is the quickest possible way to reuse code without impacting something thats working fine. You don't need to retest what was done before, and if there's a test why not copy and rename that too. The junior developer might be tempted or even guided to do this, and I've seen things like this in front office and UI development. The point of this was to suggest that the laziest solution is generally not good for the product or maintenance in the long term.

Extend Everything

At university you learn about these object things and extending them. Sounds good, so let's extend everything that means we will be able to use that useful method in this other class. This often leads to Spaghetti like code, where everything becomes tightly coupled together. Changing one part of the system can have an adverse impact on a completely different part. Thinking about composition as well as inheritance is an important lesson to learn early, ensuring that a class only actions the intended behaviour and is kept as orthogonal as possible.

Ignorance Driven Development

We don't have a product owner who is willing to be accountable for guiding the product, and they're never going to know what they want until they see it. Ok let's build something that we think they'll want and see how we go. This is often a sign of an organisational issue and though this can be a successful approach you can end up spending a lot of iterations on prototyping complex systems to find that functionality at the heart of it is really wrong. Tying down the basic requirement, even if just the initial scope should be the goal otherwise you risk a never ending sprint or product iteration.

Rabid Prototyping

Dude we've got this really complicated problem where we need to write a highly complicated algorithm to solve it. I've been working for the last 8 hours and I've come up with this sophisticated algorithm to return a single timestamp. As developers we can often be tempted to dive down a single path rapidly throwing stuff together and over complicating problems. Often the key is taking a step back or considering the options in a pair. In this case where a huge algorithm is written, it could have been simpler and made more sense to refactor to a different data structure, for example.

The Burnout Chart

How many hours have your worked this week? I'm up to 120 hours!
At the end of the day that's not a sustainable.
My day never ends, so it doesn't count!
This is a cultural issue that can be costly across a company. Things like this effectively bully developers into staying late and doing working longer or harder than they are comfortable with. In this kind of environment it's a race to who burns out or breaks down first.

Heart Break Pairing

This relates to either when a pair breaks up, or where someone is a lone wolf developer. In the break up case it makes more sense for the pair to take some cooling off time rather than arguing across the shop floor. In the imaginary friend case it's really difficult, as no one is actually available to pair or code review.

Potential Solution

After the above, without good guidance, there are many ruts developers both junior and seasoned can fall into. How can we avoid it? If you're based in London you can look to improve your skills by considering your career as a craft where you take pride in the solutions you build and deliver. The LSCC (London Software Craftsmanship Community) and the LJC (London Java Community) provide excellent platforms for this.

If you're not local to a large community group there are some excellent books that can get you started, for example The Well Grounded Java Developer is an excellent starting point. Work with your team and more experienced developers to learn from them and improve. This is by far one of the best ways to learn and improve.

The feedback from the talk was really positive and a range of people took different things from it. Some thought that methodologies are too ideal, and not indicative of the real world. I fear this is probably true for many developers, and bad habits come as a given practice. Others had seen problems like this themselves in different teams over the years, and could look back on these experiences and have a good chuckle. Others were interested in how they could improve and went away looking for books and resources to do so.

Our 3 Planned Talks for Java One

Having written about my career history and how I came to be speaking at Java One, I thought it would be useful to briefly outline what the three talks are and what we hope people will get from attending them.

Community Driving the Future of Java: Adopt a JSR - BOF4540

This BOF is an open discussion on the Adopt a JSR program, which aims at encouraging Java Community members to get involved with Java Specification Requests. We are going to highlight our journey through from starting with a lightning talk right through to working with Stephen Colebourne to help validate the design of JSR-310. We will do a small introduction on what we have worked on to set the scene and then the main focus of this talk is to discuss what people think about the Adopt a JSR and if there is more we could potentially be doing to help move this initiative forwards. If you're planning on coming along to the event, I'd recommend that you take a look at the following first to get the most out of it:

• Adopt a JSR homepage on Java.net
• 310 Adopt a JSR homepage

The event can be attended by Java developers of any level, and it would be specifically useful for members of other JUGs working on Adopt a JSR to come along to the BOF. We are hoping to have other senior LJC members in the audience with a wealth of experience when it comes to Adopt a JSR. For specific JSR-310 discussion the follow on session below will be useful too.

JSR 310: What’s Taking So Long? - BOF5127

Following on from our BOF on Adopt a JSR this BOF is on the work we have contributed to the design and testing of JSR-310 and the ThreeTen project. We want to use this session to explain and work with delegates on the complexity of developing an API that is capable of ISO-standard calendar systems, whilst making it extendable to support more complex calendar systems. It will be a great opportunity for us to dig under the covers of the new API and explain some of the decisions made. We will be joined by Roger Riggs of Oracle and we are hoping Stephen Colebourne will be along to join in the discussion. This talk is suitable for Java developers of any level who want to know more about how JSR-310 will change the way we work with dates in Java.

To get the most out of this session the following would be good pre reading materials:

• About a new date time API
• Lightning talk introduction
• ThreeTen Documentation (JavaDoc very useful at this stage)
• ThreeTen on GitHub

London Java Community: How to change the world - CONF5130

The final talk we have had accepted is based on our experiences of working as a group of developers contributing to the Java Community Process. The London Java community has more than 2000 developers and is rapidly growing, all with their own (frequently differing) opinions and ideas. Our aim has been to provide a single voice for many developers and has had many challenges along the way, but also some successes. This conference session will give you direct access to a panel of developers that have been working for the London Java Community in this capacity:

• Ben Evans
• Jim Gough
• Richard Warburton
• Trisha Gee

Come along and find out what we have been working on, what problems we have faced and how we have worked to gain success. Hopefully you will get the answer to "Is it worth it?".

Journey to Speaking at Java One 2012

Late Thursday night I received some fantastic news that Oracle had accepted 3 of my 4 submitted talks for JavaOne 2012. For me this is a milestone in my career and has been thanks to many people in the community over the past 5 years. This blog post is going to be a short tour through the last 5 years of my career, thanking certain key people along the way who have helped me to this landmark achievement.

In 2007 I graduated the University of Warwick and moved to London with a job ready to start in September. The toolbox was armed with a very broad range of practical and theoretical skills from my MEng Computer Science degree. At this stage of a graduate's career they are eager to dive right in and write as much production code as possible, I was no different. I was lucky enough to have a manager who was able to point out the craft of Software Development and how design and consideration of building products would have a significant impact in my long term career. These one hour meetings in the pub were the most valuable meetings I could have had. 

I wanted to learn more and looked for online resources. The first thing I picked up that September was a Podcast called The Java Posse - still going today and definitely worth a listen for developers of all levels. JUGs (Java User Groups) were mentioned, and I took a look to see if there was one in London and at this point was shocked that there wasn't an official or unofficial JUG I could find. As I was about to move to New York I didn't follow up on this further, continued to listen to my podcasts and built on learning to build scalable and maintainable systems within investment banks for the next 2 years.

Sometime towards the middle of 2009 I met a contractor who was active in the Java Community, he mentioned the London Java Community and another Java Community based in London. Little did I know that when I looked in September 2007, Barry Cranford a few months later had formed the London Java Community. My initial response to a recruiter running a community was apprehensive, then in late 2009 I attended my first event The Unconference and this changed everything.

I met Barry and realised this wasn't the same breed as the recruiters who phoned me up on a daily basis. It was a normal guy, a little nervous about speaking to many developers (not that you would know this now) and had worked tirelessly with friends in the community to arrange the conference. The diversity in the community right from the beginning was top of the game, everyone was welcome irrespective of background. I felt right at home, people talking about Java on a Saturday - this was amazing. Barry is to thank for starting one of the most active and successful JUGs. 

I suddenly recognised a familiar face, after a few gulps of coffee I realised it was a someone who had given me one of the most technical grillings I have ever received to date! When I say grilling I mean pushed me in an interview to bring the best out of my technical ability, and thankfully it was a successful interview. Ben Evans is one of the Java kings in London and has pushed me both technically and to contribute to the community ever since, informally a great mentor and a fantastic friend. I also met at the same time Martijn Verburg who has one of the best insights into best practices and strong development skills across the community. My work with Martijn was further in the future with the LJC JCP, and he too has been a great mentor and contributor to us making Java One.

My JUG membership for the next year was somewhat of a social one, working to greet and connect people in the community and helping to facilitate the running of the events with the LJC associates. Whilst this was fun I was looking for something that would get me more involved in the community and ultimately give me a platform to start speaking to larger audiences about Java technology and the surrounding ecosystem.

In July 2011 I started working with LJC JCP, and specifically helping to design the framework for adopting a JSR in the community. The targeted JSR was JSR-310, as Stephen Colebourne was based in the UK it made it easier for us to establish relationships. Initially as with all JSRs the main challenge is explaining the concept to other developers to maximize the input from community members. Later in 2011 I met Richard Warburton who has helped add some real power behind our Adopt a JSR efforts. The work we have done with the community and the efforts here will make up the main body of our talks for Java One. Although I had publicly spoken before, these were the first talks on Java with the community and these were well received. Following on from this we have also worked on helping with the TCK and helping validate the redesign of the API.

I'd like to thank all the people mentioned in this blog post and those that are not mentioned that have helped out along the way too, over 5 years and a short post I'm sure I have missed some people. For people who are looking to get involved in conference speaking or getting more involved and improving their Java skills I'd highly recommend working with people in your local Java User Group, as many of us in the London Java Community can testify anything is possible. Looking back on what I was thinking in 2007 I never thought the first time I was at Java One would be when I was speaking there!