can't get started with jersey user guide

Help me please. I tried for a long time to start rest app example, but I can't do this. Using jersey user guide I'm get stuck with it.Here is example:

package com.example;

import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.WebTarget;

import org.glassfish.grizzly.http.server.HttpServer;

...

public class MyResourceTest {

    private HttpServer server;
    private WebTarget target;

    @Before
    public void setUp() throws Exception {
        server = Main.startServer();

        Client c = ClientBuilder.newClient();
        target = c.target(Main.BASE_URI);
    }

    @After
    public void tearDown() throws Exception {
        server.stop();
    }

    /**
     * Test to see that the message "Got it!" is sent in the response.
     */
    @Test
    public void testGetIt() {
        String responseMsg = target.path("myresource").request().get(String.class);
        assertEquals("Got it!", responseMsg);
    }
}

but i can't realize, what is the Main class with the startServer() method? Here is no import for this class.

Here is the link for the Main class. The Main.startServer() looks like this:

/**
 * Starts Grizzly HTTP server exposing JAX-RS resources defined in this application.
 * @return Grizzly HTTP server.
 */
public static HttpServer startServer() {
    // create a resource config that scans for JAX-RS resources and providers
    // in $package package
    final ResourceConfig rc = new ResourceConfig().packages("$package");

    // create and start a new instance of grizzly http server
    // exposing the Jersey application at BASE_URI
    return GrizzlyHttpServerFactory.createHttpServer(URI.create(BASE_URI), rc);
}