Jpa

I have written about other software system analyzing and validation tools before but today I would like to introduce a new tool named jqAssistant that supports software architects, developers and analysts in a variety of tasks like analyzing given structures, validating architectural or quality constraints and generating reports. Therefore jqAssistant analyzes given projects or artifacts and stores the gathered information – that is enriched by a variety of existing plugin-ins – in a Neo4j graph database. ...

I have written about other database migration frameworks before but in this article I’d like to cover the Liquibase framework in combination with WildFly as Java EE 7 compatible application server. In the following tutorial, we’re going to write a full Java EE 7 book store application with a few steps and with Liquibase on board to create the database structure and insert example data into the database. Thanks to the WildFly Maven Plug-in we even do not need to download and configure the application server but let Maven and the plug-in do the work for us. ...

Using the Java Persistence API and a decent persistence provider allows us to configure and fine-tune when and how the second level cache is used in our application. In the following short examples, we’re going to demonstrate those features written as JUnit test cases and running on a H2 in-memory database. Figure 1. Persistence Unit Configuration Setup First of all we need some basic setup to run the following examples .. we need to select a JPA persistence provider and database, create a persistence-unit configuration and an environment to run tests on an in-memory database. ...

Querydsl is a framework that allows us to create elegant, type-safe queries for a variety of different data-sources like Java Persistence API (JPA) entities, Java Data Objects (JDO), mongoDB with Morphia, SQL, Hibernate Search up to Lucene. In the following tutorial we’re implementing example queries for different environments – Java Persistence API compared with a JPQL and a criteria API query, mongoDB with Morphia and last but not least for Lucene. ...

I really love Arquillian to run integration tests for my Java EE applications – especially when running on different containers – and I also love the Arquillian tool stack from Arquillian Drone to the Arquillian Persistence Extensions. Today I’d like to share a short snippet how to achieve transaction rollbacks when testing an EJB in combination with Arquillian and the Arquillian Transaction Extension… Arquillian Basics If you’ve never heard of the Arquillian framework before, please feel free to have a look at the Arquillian documentation or an article of mine: Arquillian Tutorial: Writing Java EE 6 Integration Tests and more... ...

Database migrations often are a necessity in the application development and maintenance life-cycle. Whenever we need to apply changes to the database structure, insert new data fragments and in doing so want to be sure that this all happens with some control and versioning. The following tutorial shows how implement this for a simple Java EE 6 web application to be run on a GlassFish application server in a few quick steps using the Flyway framework, an eager initialized Singleton EJB and some Maven wiring. ...

One common question that you may encounter one day when using object-relational-mapping in your application is how to slim down data that you’re retrieving from the persistence layer down to a specific subset for your use-case in an efficient manner and without using complex additional mapping frameworks. In some situations you might declare lazy loaded fields but another approach that I’d like to share with you here are JPA2 constructor expressions. ...

The ability to attach lifecycle events to an entity using simple annotations sometimes is a neat feature in the Java Persistence API. The following short snippets demonstrate how to bind and trigger the different available lifecycle events using an embedded derby database and a bunch of annotations. Dependencies I’m using Hibernate as persistence manager here and Derby as an easy to setup database. In the last step we’ll be writing a test that’s why we’ve added JUnit and Hamcrest. ...

Now that the long awaited stable version of the Arquillian framework is released I wanted to demonstrate some interesting features of this framework that really eases writing and running of integration tests for Java EE 6 applications in many different ways. In the following tutorial we are going to create some real-world examples using Enterprise JavaBeans, Contexts and Dependency Injection, the Java Persistence API and we’re finally running Drone/Selenium tests against a JEE Web Application that is using Java Server Faces. ...

In today’s tutorial we’re exploring the world of faceted searches like the one we’re used to see when we’re searching for an item on Amazon.com or other websites. We’re using Hibernate Search here that offers an API to perform discrete as well as range faceted searches on our persisted data. Maven Dependencies Needed For simplicity’s sake am I going to use an HSQL database for persistence, in addition the dependencies for hibernate-entitymanager and hibernate-search (of course) should be added to your pom.xml ...