Loading of spring beans in a Servlet

Hi Folks,

I am back with a simple topic of how to load spring beans in a servlet. The provision is already present without the need to access the beans using WebApplicationContextUtils i.e. by implementing a factory class something like below:

1:  public class ServiceFactory {  
2:      public static RegistrationService getRegistrationService() {  
3:         RegistrationService registrationService = new RegistrationServiceImpl();  
4:      return registrationService;  
5:    }  
6:  }  

And then in a servlet calling this service like below:

1:  boolean saved = ServiceFactory.getRegistrationService().saveNewRegistration(user);  

But as another alternative if I want to invoke the spring beans using WebApplicationContextUtils will be something like below:

1:  RegistrationService registrationService;  
2:  @Override  
3:    public void init(ServletConfig config) throws ServletException {  
4:         super.init(config);  
5:         WebApplicationContext factory = WebApplicationContextUtils.getWebApplicationContext(config.getServletContext());  
6:         registrationService = factory.getBean(RegistrationService.class);  
7:    }  

And then use it like below:

1:  boolean saved = registrationService.saveNewRegistration(user);  

In order to achieve this we need to modify our web.xml like below:

1:   <context-param>  
2:        <param-name>contextConfigLocation</param-name>  
3:          <param-value>/WEB-INF/spring-context.xml</param-value>  
4:   </context-param>  
5:   <context-param>  
6:      <param-name>log4jConfigLocation</param-name>  
7:      <param-value>/WEB-INF/log4j.xml</param-value>  
8:   </context-param>  
9:   <listener>  
10:      <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>  
11:   </listener>  
12:   <listener>  
13:             <listener-class>  
14:                  org.springframework.web.context.ContextLoaderListener  
15:             </listener-class>  
16:   </listener>   

That’s all folks by having the above changes you should now be able to access spring beans in a servlet. Please get me in touch if you find any difficulty.