https://kuelzer.ca/tags/dependency-injection/Recent content in Dependency Injection on ilikeorangutansHugoen© 2026 Jakob KülzerSun, 12 Apr 2026 14:27:24 -0400https://kuelzer.ca/posts/2012/12/11/google-guice-and-scope-mixing/Tue, 11 Dec 2012 13:59:40 -0400https://kuelzer.ca/posts/2012/12/11/google-guice-and-scope-mixing/<p>I&rsquo;ve been working on a small Java application I wrote a few years ago for some bug fixes and in the process of making it better, I introduced <a href="https://code.google.com/p/google-guice/">Google Guice</a>, my favourite dependency injection framework. On of the great features of Guice is that it supports different <a href="https://code.google.com/p/google-guice/wiki/Scopes">scopes for injection</a>. Per default, Guice will return a new object for every request. But sometimes you want to objects to be created a bit less liberally, for example, you want a certain object to be created only once. Guice has a <code>@Singleton</code> scope for that. Want an object to be created once for a request? Guice and <a href="https://code.google.com/p/google-guice/wiki/Servlets">guice-servlet</a> offers <code>@RequestScoped</code> and <code>SessionScoped</code>. But there&rsquo;s more, need JUnit per test scope? <a href="https://code.google.com/p/guiceberry/">Guiceberry</a> has exactly that: <code>@TestScoped</code> that will make sure every test gets exactly one object.</p>