Have you had that feeling that you have to write too much code to build simple functionality? Some things just feel repetitive, they feel you should be not have to write them yourself, instead a framework should make your life easier. Recently I’ve been building a project in Java/Spring, and after some time I started wondering […]
Using Spring Session for concurrent session control in a clustered environment
For a long time, Spring Security has provided support to limit the number of sessions a single user can have concurrently. This prevents users from being logged in from many different devices at the same time, for example to ensure that they won’t share their credentials to a paid site with their friends and family. […]
Spring-AMQP and payload validation: some notes from the trenches
It’s been a while since I’ve written one of our from-the-trenches blogs: that’s mostly because I’ve been very busy in those trenches developing systems for our customers. This week I completed a Spring Boot-based microservice which is responsible for interacting with some 3rd party SOAP service: its own clients communicate with it by sending request […]
Booting your Microservices Architecture with Spring and Netflix: the aftermath
On 25 November Trifork hosted a webinar in which I gave a short overview of Spring Cloud and its support for the Netflix OSS stack, focusing on Spring Cloud Config and the support for Netflix’s Eureka, Ribbon and Hystrix. We’ve been investigating this stack over the last couple of months and are using parts of […]
City-wide crowd management in Amsterdam
As most residents and visitors of Amsterdam know, every year more people are visiting Amsterdam, city wide events like GayPride, Koningsdag and MuseumNacht are getting bigger and more frequent, putting more strain on the city’s infrastructure and all people living in the city center. That’s why this November 7th, Amsterdam Marketing organized the Museumn8 hackathon […]
Documenting your REST APIs
Whenever you deliver some API that is to be consumed by another party, you will get the inevitable question of providing documentation. Probably every developer’s least favorite task. In Java there is javadoc, but that doesn’t cut it if you are delivering a Web Service API. In that realm we already know WSDL for SOAP based […]
Active cache eviction with Ehcache and Spring Framework
Caching is an essential to the majority of web applications. Let’s face it: most of the work done in an average web application (especially public ones) is repetitive, either the same user requesting the same information multiple times, or multiple users requesting the same information. The question is always: “How long do I cache”? We […]
Integrating Flyway In A Spring Framework Application
This post is about how to integrate Flyway into a Spring/JPA application for database schema migration. To skip all the preambles and get straight to the instructions, jump to Project’s Dependencies Set-up Flyway is a database migration tool which helps do to databases, what tools like git/svn/mercurial does for source code…which is versioning. With Flyway you […]
Elasticsearch, Spring MVC & Sencha Touch 2 in the Cloud – Part 2
This is the second part of my blog on how to develop an application using Elasticsearch, Spring MVC and Sencha Touch 2. In my previous blog post part 1 I showed and explained which technologies I used to accomplish the connection between the frontend and backend. In addition I presented the steps to connect a […]
Session Timeout and Concurrent Session Control with Spring Security and Spring-MVC
A web application me and my team are building recently underwent a security review. As usual, because you haven’t yet had time to put any real effort into it, some security risks did surface. We use Spring Security and Spring-MVC and I will talk about implementing a session timeout and concurrent session control: nice subjects […]