Few days ago, during our regular code review, one of my colleagues raised a question what would happen – and if it’s even possible – when a CDI Observer (so a method with parameter annotated @Observes) would be invoked multiple times at the same time for different event instances. In other words, after producing few events, is it possible that the following method will be processed by more than one thread at the same time:...
JPA specification defines few types of EntityManagers / Persistence Contexts. We can have: extended and transactional-scoped EntityManagers, container-managed or application-managed EntityManagers. JTA or resource-local EntityManager, Besides the above distinction, we also have two main contexts in which EntityManager / Persistence Context can exist – Java EE and Java SE. Not every option is available for Java EE and not every is possible in Java SE. In the rest of the post I refer to the Java EE environment....
More than 18 months ago I’ve posted my mock exam for Oracle Certified Expert Web Component Developer certification. Until now it’s quite popular and useful (deducting from the comments) for many of you. What I dislike about this exam is that it’s published as a plain WordPress post and it’s rather awful to edit it and it’s not so easy to read as well. So, that’s the aim of my small side project: to create a basic platform for presenting exam questions and their answers....
The aim of this post is to show you how, using CDI, you can inject Java properties entries (those in *.properties files) directly into your Java class. This is somewhat similar to the Spring’s @Value annotation I needed in my plain Java EE project. The whole code can be found on GitHub so feel free to clone it, use it or make any changes you like. Context Ok, so basically in a Java EE environment we already have a way to define some properties that are deployment-specific – it’s the <env-entry> element in the descriptor....