Are you ready?
If so, let’s start with the first element of the puzzle.
Whether you like it or not, software development is a collaborative activity. Integration work has always been demonized and treated as necessary evil. There are several approaches which try to solve the challenge of effective integration. The feature toggle belongs to that group. In this article, you’ll see in practice how feature toggles, also known as feature flags, can be used in your Spring Boot application.
Continue reading “Feature toggle in Spring Boot 2”
It’s been almost two years since Java 8 was officially released and many excellent articles about new enhancements and related best practices have been written through that time. Surprisingly, one of the more controversial topics amongst all the added features is the Optional class. The type is a container, which can be either empty or contain a non-null value. Such construction reminds the user of an Optional object that the situation when there’s nothing inside must be handled appropriately. Although the definition of the type on Javadoc is quite descriptive, when it comes to identifying valid use cases it’s getting more problematic.
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Sending an email from the backend application part is a quite common use case in the world of enterprise applications. Although HTML content isn’t standardized message format, numerous mail clients support at least a subset of the markup language. In this post you will learn how to send an HTML email using Spring Boot standard modules and prepare an HTML content for a message using Thymeleaf template engine.
Continue reading “Sending HTML email with Spring Boot and Thymeleaf”
Although built-in validation support in Spring is largely sufficient for standard use cases, sooner or later you will run into a situation when the sets of validation annotations provided by JSR 303 or Hibernate Validator aren’t enough. In this post you will learn how to create a simple constraint annotation served by a custom validator with access to the Spring context of a Spring Boot application.
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As software developers, we always look for opportunities to improve our efficiency at work and optimize repeatable activities. One of them is application startup. Even if you cover your production code with unit tests and follow TDD, from time to time checking how the whole application works is inevitable. The more often you run it, the more time is wasted on waiting until the application is ready to operate.
Although the fast restart provided by Spring Boot DevTools is helpful for library class loading, it doesn’t solve the issue with the long startup of your own application code. From this post you will learn how to decrease the total number of coffee breaks in daily work by configuring faster Spring Boot startup in your local development environment.
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The Spring framework with almost no effort can solve for you many common programming problems, but some of its features are less known than others. In this post, we’re going to take a close look at the @Lazy annotation, which belongs to this group. After reading several examples, you should be able to apply the annotation to your daily development tasks.
Continue reading “Spring @Lazy annotation use cases”
Although the total number of acronyms in the programing industry has probably already exceeded the number of stars observable on the moonless night sky, only a subset has gained popularity and recognition. TDD definitely belongs to this group. Judging by numerous conference lectures, books, podcasts, and blog posts, the fact that Test Driven Development is a widely known technique is rather undeniable. Yet, when you consider its adoption and actual usage the reality might look a bit different. In this article we will take a look at the different reasons for avoiding TDD that have been presented by candidates during several conducted technical interviews and try to disprove if they are real obstacles.
Continue reading “Why developers don’t use TDD”
Spring Cloud solves common problems of distributed systems. However, for someone who works only with widely known monolith applications jumping into the long list of patterns designed for distributed services might be quite overwhelming at the very beginning. This article will take you through the basics of Spring Cloud by taking a practical approach. After finishing, not only should you know how to start a project based on Spring Cloud, but also understand why all steps are required and what problems they solve.
Continue reading “Spring Cloud basic setup”
The package is a fundamental concept in Java and one of the first things you stumble upon when starting programming in the language. As a beginner you probably don’t pay much attention to the structure of packages, but as you become a more experienced and mature software developer, you start to think what can be done to improve their efficiency. There are a few major options to consider and picking the right one might not be an obvious choice. This article should give you an overview of commonly selected strategies.
Continue reading “Project package organization”