Generating PDFs with Java, Flying Saucer and Thymeleaf

Generating PDFs can by a tough job. If you ever worked with templating engines like Jasper you probably know what I mean. On the other side, HTML makes it extremely simple to describe documents. So why not use HTML to generate PDFs? The following post shows a simple approach to generate PDFs with Thymeleaf templates […]

Effective error handling for ActiveMQ topics

No matter what type of software you make, there will always be errors. There might be bugs in your code or an external system is just down at the moment. No matter what it is, it will cause you trouble. Asynchronous messaging (with JMS) might help to deal with such situations. Especially when you depend […]

Virtual Topics in ActiveMQ

A couple of days ago I published a post about the difference between queues, topics and virtual topics. Today I want to share some practical information on how to use virtual topics in ActiveMQ with Spring Boot. Virtual Topics Virtual topics are a combination of topics and queues. Producers will write messages to a topic […]

Queues vs. Topics vs. Virtual Topics (in ActiveMQ)

ActiveMQ provides a variety of different messaging patterns. While queues and topics are the most famous ones, virtual topics can combine the best of both worlds: multiple consumers with their own dedicated queue. Queues Queues are the most obvious messaging pattern implemented by ActiveMQ. They provide a direct channel between a producer and a consumer. […]

Login by captcha and authenticate with JSON Web Token

We use a login to secure our application and restrict its access to a certain group of users. But what if everybody should be allowed to use our application if he can prove he’s human? Well, we would use a captcha. The following example shows how we can use Google’s ReCaptcha for an anonymous login […]

Using @ConfigurationProperties to separate service and configuration

Roughly about two years ago, I wrote an article called “Why using Spring’s @Value annotation is bad“. I described why you should avoid @Value annotations all throughout your code. By using @Value annotations in services, controllers and other Spring components, you will scatter your configuration through the complete application. In the worst case, you will […]

The Disqus Affiliated Links Program

Yesterday, I received an e-mail from somebody who read an article on my blog. He told me that he clicked on the XING link on my “About” page, but was redirected to some shady online trading website instead of my XING profile. So I took my laptop and reviewed my own blog, immediately. And – […]

AngularJS tests with mocked HTML documents

Most of the time, testing AngularJS applications means testing JavaScript. We test services and we test controllers. But what about directives? What about components? How do we test compiled and injected AngularJS code? Plunker But before we start, here’s the running Plunker with the complete example: https://plnkr.co/edit/PKn4tpUDFWyeqJ2Tb7Ba Testing directives/components Around a year ago I wrote […]

Coursera Full Stack Web Development Course Review

During the last 6 months I did the Full Stack Web Development course on Coursera. Since I’m currently about to finish the course by implementing my final capstone project (https://github.com/tuhrig/mebo), I wanted to share my thoughts about the course and its pros and cons. About the course The Full Stack Web Development course consists of […]