Spring injection Into Servlet

Question

So I have seen this question:

Spring dependency injection to other instance

and was wondering if my method will work out.

1) Declare beans in my Spri

Answer 1

The answers here so far only worked partly for me. Especially classes with @Configuration annotation were ignored and I did not want to use an xml configuration file. Here is what I have done to get injection working working soley with an Spring (4.3.1) annotation based setup:

Bootstrap an AnnotationConfigWebApplicationContext in web.xml under web-app. As parameter you need the contextClass and the contextConfigLocation (your annotated config class):

    contextClass
    
org.springframework.web.context.support.AnnotationConfigWebApplicationContext
  


    contextConfigLocation
    com.example.config.AppConfig


    org.springframework.web.context.ContextLoaderListener

Then overwrite the init method in the servlet. I use an abstract class which extends HttpServlet, so I don't have to repeat it in every servlet:

@Configurable
public abstract class MySpringEnabledServlet extends HttpServlet
{
  @Override
  public void init(
      ServletConfig config) throws ServletException
  {
    super.init(config);
    SpringBeanAutowiringSupport.processInjectionBasedOnCurrentContext(this);
  }
[...]
}

and finally I have my main configuration in the AppConfig class mentioned in web.xml:

@Configuration
@ComponentScan(basePackages = "com.example")
@Import(
{ SomeOtherConfig.class })
public class AppConfig
{
}

The dependend classes are annotated:

@Component
public class AnnotatedClassToInject

and injected via autowiring in my servlet:

@Autowired
private AnnotatedClassToInject myClass;