UserDAO covered by jUnit test example

import com.mongodb.*;
import course.UserDAO;
import org.junit.After;
import org.junit.BeforeClass;
import org.junit.Test;

import java.net.UnknownHostException;

import static org.junit.Assert.*;

public class UserDAOTest {
    static MongoClient mongoClient;
    static DB blogDatabase;
    static DBCollection usersCollection;
    static UserDAO userDAO;

    // this method called before all test (once), to initialize DB variables
    @BeforeClass
    public static void setUp() throws UnknownHostException {
        mongoClient = new MongoClient();
        blogDatabase = mongoClient.getDB("blog");
        usersCollection = blogDatabase.getCollection("users");
        userDAO = new UserDAO(blogDatabase);
        usersCollection.drop();
    }

    //this method calls after every test to clean usersCollection
    @After
    public void dropCollection(){
        usersCollection.drop();
    }

    @Test
    public void addUserTest()  {
        System.out.println("Starting test on adding user");

        String email =  "b1102@email.ru";

        userDAO.addUser("b1102" , "1111" , email );

        DBObject find   = new BasicDBObject("_id" , "b1102" );

        DBObject user = usersCollection.find(find).next();

        assertTrue(user.get("email").equals(email));

        System.out.println("User successfully added");
        System.out.println("");

    }

    @Test
    public void addUserThatExistsTest() throws UnknownHostException {
        System.out.println("Starting test on adding user that already exists");

        String email =  "b1102@email.ru";

        userDAO.addUser("b1102", "1111", email);
        assertFalse(userDAO.addUser("b1102", "dedede", "e3r3r"));

        System.out.println("Test on adding user that already exists passed");
        System.out.println("");

    }

    @Test
    public void CheckUserPassPositive() throws UnknownHostException {
        System.out.println("Starting positive test on checking user's pass");
        String login = "b1102";

        String email =  "b1102@email.ru";
        userDAO.addUser(login, "1111", email);

        DBObject validatedUser = userDAO.validateLogin(login , "1111");
        DBObject foundUser = usersCollection.find(new BasicDBObject("_id" , login)).next();

        assertEquals(foundUser, validatedUser);

        System.out.println("Positive test on checking user's pass passed");
        System.out.println("");

    }

    @Test
    public void CheckUserPassNegative() throws UnknownHostException {
        System.out.println("Starting negative test on checking user's pass");
        String login = "b1102";

        String email =  "b1102@email.ru";
        userDAO.addUser(login, "1111", email);

        assertNull(userDAO.validateLogin(login , "1112"));

        System.out.println("Negative test on checking user's pass passed");
        System.out.println("");

    }


    @Test
    public void GetNotExistUser() throws UnknownHostException {
        System.out.println("Starting test on getting not exists user");
        String login = "b1102";

        String email =  "b1102@email.ru";
        userDAO.addUser(login, "1111", email);

        assertNull(userDAO.validateLogin(login+"1" , "1111"));

        System.out.println("Test on getting not exists user passed");
        System.out.println("");

    }

}