package com.zangolie.smallbiz.services.rest; import java.net.URI; import java.util.Collection; import javax.ejb.Stateless; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; import javax.persistence.TypedQuery; import javax.ws.rs.BadRequestException; import javax.ws.rs.Consumes; import javax.ws.rs.DELETE; import javax.ws.rs.GET; import javax.ws.rs.NotFoundException; import javax.ws.rs.POST; import javax.ws.rs.PUT; import javax.ws.rs.Path; import javax.ws.rs.PathParam; import javax.ws.rs.Produces; import javax.ws.rs.core.Context; import javax.ws.rs.core.MediaType; import javax.ws.rs.core.Response; import javax.ws.rs.core.UriInfo; import com.zangolie.smallbiz.entities.Item; @Path("/item") @Produces ({MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML}) @Consumes ({MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML}) @Stateless public class ItemRestService { //the PersistenceContext annotation is a shortcut that hides the fact //that, an entity manager is always obtained from an EntityManagerFactory. //The peristitence.xml file defines persistence units which is supplied by name //to the EntityManagerFactory, thus dictating settings and classes used by the //entity manager @PersistenceContext(unitName = "testPU") private EntityManager em; //Inject UriInfo to build the uri used in the POST response @Context private UriInfo uriInfo; @POST public Response createItem(Item item){ if(item == null){ throw new BadRequestException(); } em.persist(item); //Build a uri with the Item id appended to the absolute path //This is so the client gets the Item id and also has the path to the resource created URI itemUri = uriInfo.getAbsolutePathBuilder().path(item.getId()).build(); //The created response will not have a body. The itemUri will be in the Header return Response.created(itemUri).build(); } @GET @Path("{id}") public Response getItem(@PathParam("id") String id){ Item item = em.find(Item.class, id); if(item == null){ throw new NotFoundException(); } return Response.ok(item).build(); } //Response.ok() does not accept collections //But we return a collection and JAX-RS will generate header 200 OK and //will handle converting the collection to xml or json as the body @GET public Collection getItems(){ TypedQuery query = em.createNamedQuery("Item.findAll", Item.class); return query.getResultList(); } @PUT @Path("{id}") public Response updateItem(Item item, @PathParam("id") String id){ if(id == null){ throw new BadRequestException(); } //Ideally we should check the id is a valid UUID. Not implementing for now item.setId(id); em.merge(item); return Response.ok().build(); } @DELETE @Path("{id}") public Response deleteItem(@PathParam("id") String id){ Item item = em.find(Item.class, id); if(item == null){ throw new NotFoundException(); } em.remove(item); return Response.noContent().build(); } }