@GET @ApiIgnore // until documented
  @Path("{instanceID}")
  @Produces("text/plain")
  public Response getInstance(String body, @Context HttpHeaders headers, @Context UriInfo ui,
                          @PathParam("instanceID") String instanceID) {

    return handleRequest(headers, body, ui, Request.Type.GET,
        createInstanceResource(m_feedName, instanceID, ui));
  }
Handles GET /feeds/{feedID}/instances/{instanceID} and /instances/{instanceID}
Get a specific instance.

@param headers     http headers
@param ui          uri info
@param instanceID  instance id

@return instance resource representation
ambari-server/src/main/java/org/apache/ambari/server/api/services/InstanceService.java