Deploying Jersey resources on Servlet 3.0 container

The common way to deploy a Jersey REST resource is to configure the web.xml file so that there is a servlet container responsible to delegate requests from a specific URL pattern to resource classes. If you use a Servlet 3.0 container, for example Tomcat 7, it is possible to use Java annotations rather than aweb.xml file. Oddly enough, there is not much information available on how to configure Jersey by using annotations.

First, you need a class that extends class Application and that has to be annotated with @ApplicationPath. The value of the annotation is the base path of the REST service that is to be managed by this class. This class must override method getClasses that returns a set of classes that provide the implementation of the endpoints of this REST service. This is comparable to the declaration of packages that was used previously in the web.xml file.

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@ApplicationPath( "rest" ) public class RestService extends Application { public RestService( ) {}   @Override public Set<Class<?>> getClasses( ) { final Set<Class<?>> returnValue = new HashSet<Class<?>>( ); returnValue.add( Resource.class ); return returnValue; } }

Class Resource implements the REST service and has to be annotated with @Path on the class level. This is very important. If this annotation is missing, the REST service cannot be accessed.

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@Path( "/hello" ) public class Resource { public Resource( ) {}   @GET @Produces( "text/html" ) public String printHelloWorld( ) { return "Hello World"; } }

The URL to access the REST service is http://localhost:8080/api/rest/hello, provided that api is the path under which this project was deployed into the Tomcat container. When you open this URL in a Web browser, you should see the Hello World message.

original link:

http://peter-braun.org/2013/03/deploying-jersey-resources-on-servlet-3-0-container/