Up until Spring 4 generics played no major role when it came to resolving injected bean dependencies. Suppose there are multiple beans of the same type implementing a generic interface. In a pre-Spring 4 world, any attempt to resolve such a bean by type would inevitably lead to a NonUniqueBeanDefinition exception, unless additional hints were…
I’ve got the aforementioned exception when I was trying to load a jsp page on Tomcat 6 running in a debug mode. Turns out the problem occurs when a jsp page grows big. It’s a known JVM issue described by bugs 39089 and 6294277. Here is how to solve it without touching the jsp. Open conf/web.xml In your…
Less unit test code doesn’t necessarily result into poor coverage. I’ve recently entered the paradigm of parameterized tests when refactoring a larger test suite. I ended up writing significantly less code without compromising on the extent. In fact, adding a few corner cases was almost a no-brainer. In this post I’d like to share my…
In this post, I will look into the distinction between a component and a bean. Even though both of them refer to Spring managed beans, each serves a different purpose. @Component and its specializations (@Controller, @Service and @Repository) allow for auto-detection using classpath scanning. @Bean on the other hand can only be used to explicitly…
Last time, when I talked about lazily loaded beans I forgot to mention one interesting feature of Spring 4 – lazily loaded injection points. This post introduces the combination of @Lazy and @Autowire as a counterpart to the standard approach (JSR-330) using @Inject and Provider. As of Spring 4.0 @Lazy can be applied on injection…
Lazy initialization allows for a greater flexibility and performance by delaying bean instantiation to the very last moment. A fairly straightforward feature represented by a simple annotation @Lazy. Yet, as usual, there are a few pitfalls to watch out for. Let’s start with some trivia. Adding @Lazy on the class level is all it takes…