My place on the internet where I occasionally write about Java / Spring Software Development https://deinum.biz/ When you use Spring (Boot) you inevitably come around or will use the @ComponentScan annotation to automatically detect your classes (meta) annotated with @Component. Lets take a look at a basic Spring Boot sample that will detect our @Component annotated classes. Lets write an application that uses a Printer to... Fri, 05 Nov 2021 00:00:00 +0100 https://deinum.biz/2021-11-05-Component-Scanning/ https://deinum.biz/2021-11-05-Component-Scanning/ Before diving in let’s take a look at two definitions of dependency injection (according to Wikipedia). Dependency Injection is a technique in which an object receives other objects that it depends on. These other objects are called dependencies. – Wikipedia Dependency injection is one form of the broader technique of... Tue, 28 Jul 2020 00:00:00 +0200 https://deinum.biz/2020-07-28-Dependency-Injection/ https://deinum.biz/2020-07-28-Dependency-Injection/ A commonly asked question on sites like StackOverflow is “Why is the field i’m autowiring null”. When this happens it generally is an error of the user as an autowired field in Spring cannot be null. At startup Spring will try to satisfy all the dependencies of a bean, if... Fri, 03 Jul 2020 00:00:00 +0200 https://deinum.biz/2020-07-03-Autowired-Field-Null/ https://deinum.biz/2020-07-03-Autowired-Field-Null/ When using Spring Boot or just plain Spring Framework it might be that you want to delay the startup of your application until a proper connection to the database can be made. This might be even more the case when using container technologies, like Docker. I recently came across the... Tue, 30 Jun 2020 00:00:00 +0200 https://deinum.biz/2020-06-30-Wait-for-database-startup/ https://deinum.biz/2020-06-30-Wait-for-database-startup/ When working on an existing application using an older version of the Spring Framework (aka Spring) it might be time to upgrade. Although in most cases upgrading to a newer version of Spring is a matter of changing the version. When doing a large upgrade, like from 2.5 to 5.1,... Fri, 21 Jun 2019 00:00:00 +0200 https://deinum.biz/2019-06-21-Upgrade-Spring-Framework-In-Existing-Application/ https://deinum.biz/2019-06-21-Upgrade-Spring-Framework-In-Existing-Application/ When using a framework like Lombok it is very tempting and easy to use its @Data annotation. All together now: A shortcut for @ToString, @EqualsAndHashCode, @Getter on all fields, @Setter on all non-final fields, and @RequiredArgsConstructor! (Source: Lombok Documentation) TL;DR You probably don’t want to use @Data annotation with @Entity... Wed, 13 Feb 2019 00:00:00 +0100 https://deinum.biz/2019-02-13-Lombok-Data-Ojects-Arent-Entities/ https://deinum.biz/2019-02-13-Lombok-Data-Ojects-Arent-Entities/ As a developer I’m always interested in using different data access technologies instead of plain JDBC. Especially combined with Spring Boot. Recently I came across JDBI and was intested in trying it out with Spring Boot as an experiment. I created a simple order system to try it. First the... Mon, 13 Aug 2018 00:00:00 +0200 https://deinum.biz/2018-08-13-Use-JDBI-With-Spring-Boot/ https://deinum.biz/2018-08-13-Use-JDBI-With-Spring-Boot/ By default the @PropertySource annotation isn’t usable with YAML files. This is also the standard answer given when asked on, for instance StackOverflow (even by me!). But as of Spring 4.3 it’s possible to make it work. Spring 4.3 introduced the PropertySourceFactory interface. The PropertySourceFactory is a factory for a... Wed, 04 Jul 2018 00:00:00 +0200 https://deinum.biz/2018-07-04-PropertySource-with-yaml-files/ https://deinum.biz/2018-07-04-PropertySource-with-yaml-files/ There appears to be a lot of confusion in the community on how to expression bean configuration or rather how to convert bean configuration from XML to Java (or Groovy, or Kotlin, or…) as it appears as if the different ways of configuration are completely different things. But in fact... Thu, 12 Apr 2018 00:00:00 +0200 https://deinum.biz/2018-04-12-on-spring-applicationcontext-and-bean-creation/ https://deinum.biz/2018-04-12-on-spring-applicationcontext-and-bean-creation/ The Spring Framework (and its portfolio projects) contain a lot of functionality already by themselves. However there are also some nice hidden gems inside the framework, in this blog I will (un)cover a couple of them. The code for the sample(s) can be found on Github. Log incoming Requests A... Wed, 01 Jul 2015 15:11:16 +0200 https://deinum.biz/2015-07-01-spring-framework-hidden-gems/ https://deinum.biz/2015-07-01-spring-framework-hidden-gems/ After playing around with AngularJS and Yeoman at home I decided to try it out at work. To clarify @Home I use a Mac with OSX and use Homebrew to install additional packages. @Work I have a virtual workstation running Windows 7 installed. Trying out that setup on that configuration was,... Mon, 01 Jul 2013 19:46:19 +0200 https://deinum.biz/2013-07-01-yeoman-behind-a-corporate-proxy/ https://deinum.biz/2013-07-01-yeoman-behind-a-corporate-proxy/ In short Hibernate Search by Example is a great how-to guide if you quickly want to get started with Hibernate Search. Hibernate Search by Example is a thorough how-to guide to Hibernate Search. It shows and explains by clear examples how to setup and use Hibernate Search. The book is... Thu, 27 Jun 2013 19:50:33 +0200 https://deinum.biz/2013-06-27-94/ https://deinum.biz/2013-06-27-94/ Update (1-8-2012): Please download the most recent version of the sources from either the GitHub repository or from the Apress website. This version fixes the problem with the project dependencies. You arrived at this page because of 2 reasons. First you bought Pro Spring MVC: with Web Flow for which I... Mon, 30 Jul 2012 20:24:30 +0200 https://deinum.biz/2012-07-30-pro-spring-mvc-with-web-flow-sample-application-fails-to-start/ https://deinum.biz/2012-07-30-pro-spring-mvc-with-web-flow-sample-application-fails-to-start/ Spring Security 3 is a pretty decent book if you want to get started with Spring Security or want to know more of the internals or exotic features it has to offer. The book starts with a brief explanation of the different parts of secutiry and after that explains how... Sun, 07 Nov 2010 11:21:01 +0100 https://deinum.biz/2010-11-07-56/ https://deinum.biz/2010-11-07-56/ This book sets out to explain the usage of hibernate with the spring framework. This is basically done in the first chapters. It explains how to configure hibernate from within a spring ApplicationContext and it explains how to write a dao. To bad that, for the dao, they still use... Fri, 05 Nov 2010 11:25:25 +0100 https://deinum.biz/2010-11-05-spring-persistence-with-hibernate/ https://deinum.biz/2010-11-05-spring-persistence-with-hibernate/ A couple of months ago I wrote a step 1 on migrating a classis J(2)EE application to a spring based application. Recently I had some time again on my hands and after studying the application and also after some discussions I had I decided to structure the project a little... Fri, 02 Oct 2009 19:10:45 +0200 https://deinum.biz/2009-10-02-migrate-classic-j2ee-to-spring-step-1-revised/ https://deinum.biz/2009-10-02-migrate-classic-j2ee-to-spring-step-1-revised/ A few weeks ago I was contacted by packt publishing to review one of their books. They asked me if I wanted to review Spring Web Flow 2 Web Development (sample chapter). In short the book consists of 254 pages in all those pages they try to explain Spring Web... Mon, 25 May 2009 08:59:27 +0200 https://deinum.biz/2009-05-25-spring-web-flow-2-web-development/ https://deinum.biz/2009-05-25-spring-web-flow-2-web-development/ A few months ago SpringSource released a white paper describing the migration from J2EE to a Spring framework based application. Even before they wrote that white paper I already had the idea of writing something about how to migrate from J2EE to a Spring based application. However Colin Sampaleanu (at... Wed, 06 May 2009 13:10:45 +0200 https://deinum.biz/2009-05-06-migrate-classic-j2ee-to-spring/ https://deinum.biz/2009-05-06-migrate-classic-j2ee-to-spring/ It seems quite hard to configure a JNDI Resource in Tomcat. Especially when it comes to configuring XA capable resources. The key lies in understanding how Resources work/need to be configured. A Resource has a few properties which are used by Tomcat, those are the auth, name, description, scope and... Mon, 14 Jan 2008 14:40:54 +0100 https://deinum.biz/2008-01-14-configuring-jndi-resources-in-tomcat/ https://deinum.biz/2008-01-14-configuring-jndi-resources-in-tomcat/ Well that is the title of the presentation I just gave at the NL-JUG 2007 conference. The presentation was about the Spring Web Flow solution we created to secure flows. The presentation can be found and the conference website. The code is available in the JIRA under issue SWF-93 but... Wed, 13 Jun 2007 11:58:31 +0200 https://deinum.biz/2007-06-13-securing-spring-web-flow/ https://deinum.biz/2007-06-13-securing-spring-web-flow/