I had an opportunity to participate in the Spring I/O 2015 conference in Barcelona [1]. I was there with some guys from my work. This was a 2-day conference. The event was mainly focused on spring-related products. It was expected 
Organizers say about it 2 days full of Spring, Groovy, Grails and Cloud. In general, opinions expressed in this post are based on my observations of facts and presentations which I saw. I can say that the atmosphere was good enough. My general feeling is positive. We should take into account the duration, organization, purpose and price in order to evaluate the event.
Place
It took place in AXA Auditorium, Av. Diagonal 547, Barcelona. It was a nice place for it. It started on 29th of April and ended on 30th of April. Usually conferences take three days and one or two days for additional workshops. Here it all fits in two days. This duration may be appropriate for narrow spectrum of topics.
Content
It was not a conference about software development in general. Selected topics were specific.There were four parallel tracks. Tracks 1-3 provided regular presentations while the forth was for workshops. The presentations which I attended had mostly good presenters. The presentation I mostly liked is Keynote | 12 Years of Spring: An Open Source Journey delivered by Juergen Hoeller.
Topics were focused on tooling. I mean the presentations were rather concrete and provided practical usage of tools and API’s. I would also call it a tutorial way. What was missing or maybe I missed presentations with a high level goal. Presentations about architecture, vision. It was about CRAFTSMANSHIP and there was no ART.
There was after event party on day 1. There was one drink included. We did not stay long here. After having one glass of wine we went visiting Barcelona.
Price
The price was between 109 Euro and 149 Euro depending on time in which a ticket was ordered.
Lunch
Visiting Barcelona
This trip was also a good time to visit a little bit of Barcelona. There are some pictures below.
Summary
It looks that the conference went according to the schedule [2]. The conference and place made together a good combination of event as a whole. Organizers ask for feedback in order to make the conference better next year. Would I like to go there again? Yes.
References
[1] http://www.springio.net/
[2] http://www.springio.net/agenda/