Wednesday 17 October 2012

Building a REST Java web service API using the Spring framework

Building a REST-ful Java web service API has never been more restful than now, using version 3+ of the Spring framework.

 First some annotated Java code:

@Component
@Controller()
public class SampleController {

     @Autowired
     private SampleService service;

     @RequestMapping(value = "/samples/{reference}", method = {RequestMethod.GET})
     @ResponseBody
     public Sample getSampleByReference(@PathVariable String reference) {
          return service.getSampleByReference(reference);
      }
 }

 Then some Spring config:

<beans> 
    <context:component-scan base-package="com.blah.sample" /> 
        <aop:aspectj-autoproxy /> 
</beans> 

Then some web.xml config in your web application: 

<web-app> 
    <servlet> 
        <servlet-name>dispatcher</servlet-name> 
        <servlet-class>org.springframework.web.servlet.DispatcherServlet </servlet-class>
    </servlet> 
    <servlet-mapping> 
        <servlet-name>dispatcher</servlet-name> 
        <url-pattern>/*</url-pattern> 
    </servlet-mapping> 
</web-app> 

And that's about it, folks.   Spring will automagically handle JSON and XML accept reponses depending on what's in your classpath.

A fully working sample can be found here. And of course you can then generate REST documentation using RESTdoclet.  :)  Build a Java web service has never been easier in my opinion.
Share: