Tech

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. ...

Blueprint is a new API in Confluence 5 that allows developers to create new content elements and to hook into the Confluence “create” dialogue – not to be confused with OSGi blueprints, the CSS blueprint framework or Tinkerpop Blueprints here. Content may be added using simple XHTML templates, dynamic templates enriched with data from context providers or even customized JavaScript dialogues. Another feature is, that pages of a specific blueprint type may be aggregated in a collector view that displays all pages created with the specific blueprint ...

I recently stumbled upon a nice framework that allows to convert simple JUnit tests into micro benchmarks named JUnitBenchmarks. It allows to set basic benchmark options and and to generate charts by adding some simple annotations and a test rule to your tests. One might argue if it is wise to mix the aspects, testing and benchmarking and I’d agree for sure – nevertheless I think this framework can be handy sometimes so let’s create some benchmarks using JUnit and JUnitBenchmarks.. ...

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. ...

Whenever I encounter a situation where I have to mix a blend of different services and endpoints and apply one or more of the traditional enterprise integration patterns then Apache Camel often is my weapon of choice. I simply love how easy it is to set up some datasources, add some routing magic, data transformers, load balancers, content enrichers and enjoy the result. Another thing that I’m beginning to love is Scala and so this is the perfect time to write an article about using Scala and Apache Camel together. ...

Daydream is the new interactive screensaver mode that was added in the Android 4.2 / Jelly Beans release. Such “dreams” may be activated when the device is in idle mode or inserted into a dock. In the following tutorial we’re going to create a simple daydream that starts a simple animation and in addition we’ll be adding a configuration screen to alter the behaviour of this daydream. Create a new Android Application First of all we need a new android project. I am using Eclipse and the ADT plugin here but any other solution like using a specific Maven archetype and the Jayway Maven plugin or using SBT should work, too. ...

ScalaTest is an excellent framework to write concise, readable tests for your Scala or Java code with less effort. In addition it integrates well with a variety of frameworks like JUnit, TestNG, Ant, Maven, sbt, ScalaCheck, JMock, EasyMock, Mockito, ScalaMock, Selenium, Eclipse, NetBeans, and IntelliJ. In the following short tutorial we’re going to write some tests using ScalaTest exploring features like rich matchers, BDD syntax support or web tests using Selenium/Webdriver. ...

When there is XML to be parsed sometimes we’re chosing a DOM parser, sometimes a SAX parser and sometimes we’re using an XML pull parser, especially on Android. The following short snippet shows how to use the xpp3 xml pull parse to fetch some information in xml format from a public issue tracker and to extract issue details. Adding Dependencies Just one dependency needed here: xpp3 SBT Simply use the following build.sbt ...

Managing my projects’ source code I am using Git also as Mercurial. Therefore I often encounter the situation where I am creating a special branch to implement a specific user story or feature request. Now when working on such a story branch I often enter the issue-key or a short title as a prefix for each commit message. Doing this by manually is a waste of time and error-prone and luckily for us, each of both DVCS offers us an easy API to add custom hooks to the different life-cycle events. ...

Sometimes we need to classify the tests in a project and a possible solution to achieve this goal is to assign different categories to the tests. Often we’re doing this to separate the execution of fast-running and long-running tests or to run a specific set of tests that is only applicable in special situations. To run a specific set of categorized tests there are different options and in the following tutorial we’ll be covering two of them: by configuring the Maven Surefire Plug-in or by using a JUnit Test Suite and the JUnit annotations. ...