How to run tests cases in one test

im looking for solution to run test where are included test cases from several test cases. I need to make test like this: 1.open homepage 2.click on login link 3. type login and pass + submit

I have 2 classes (pages) HomePage and LoginPage, I want to make GotoLoginPageTest and LoginTest. I dont know how to make flow to run GotoLoginPageTest and in the same browser LoginTest (2 tests cases in one test). I dont know how to addict this two tests cases. Can You tell me how do do this, or some example using pagefactory, page object? Im using maven, testng, java. My CODE:

 public class HomePage {
 WebDriver driver;  

 public static final  String PAGE_TITLE = "page title";
 public static final  String PAGE_URL = "www.blbl.pl";

@FindBy(xpath = "//*[@id='global-nav']/div/div/div[3]/ul/li[1]/a")
WebElement LogInLink;

    public HomePage(WebDriver driver){
        this.driver = driver;
    }

    public void isHomePage(){
    String pageTitle = driver.getTitle();
    Assert.assertEquals(pageTitle, PAGE_TITLE);
}

public void goToLoginPage(){
    LogInLink.click();
}

}

LoginPage

public class LoginPage {
WebDriver driver;

public static final  String PAGE_TITLE = "Login";

@FindBy(id="user_email")
WebElement inputUserEmail;

@FindBy(id="user_password")
WebElement inputUserPassword;


public LoginPage(WebDriver driver){
    this.driver = driver;
}

public void isLoginPage(){
    String pageTitle = driver.getTitle();
    Assert.assertEquals(pageTitle, PAGE_TITLE);
}

public void fillUserEmail(){
    inputUserEmail.sendKeys("asdfasd@gmail.com");
    Assert.assertEquals(inputUserEmail.getAttribute("value"), "asdfasd@gmail.com");
}

public void fillUserPassword(){
    inputUserPassword.sendKeys("123456");
    Assert.assertEquals(inputUserPassword.getAttribute("value"), "123456");
}

}

GotoLoginPageTest

import pages.HomePage;

public class GotoLoginPageTest {
    WebDriver driver;
    HomePage hp;


    @BeforeClass
    public void setup(){
        this.driver = new FirefoxDriver();
        hp = PageFactory.initElements(driver, HomePage.class);
        driver.get(HomePage.PAGE_URL);
    }

    @Test(priority = 1)
    public void isHomePage(){
        hp.isHomePage();
    }

    @Test(dependsOnMethods = "isHomePage")
    public void gotoLoginPage(){
        hp.goToLoginPage();
    }

}

LoginTest

public class LoginTest {
    WebDriver driver;

    LoginPage lp = PageFactory.initElements(driver, LoginPage.class);

    @Test
    public void cheskIsLoginPage(){
        lp.isLoginPage();
    }

    @Test
    public void logInBase(){
        lp.fillUserEmail();
        lp.fillUserPassword();
    }

}

my testng.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suite SYSTEM "http://ift.tt/19x2mI9">
<suite name="Suite" parallel="none">
  <test name="Test">
    <classes>
      <class name="tests.GotoLoginPageTest"/>
      <class name="tests.LoginTest"/>
    </classes>
  </test> <!-- Test -->
</suite> <!-- Suite -->

GotoLoginPageTest pass but LoginTest fail, I have error java.lang.NullPointerException.

java.lang.NullPointerException
at org.openqa.selenium.support.pagefactory.DefaultElementLocator.findElement(DefaultElementLocator.java:69)
at org.openqa.selenium.support.pagefactory.internal.LocatingElementHandler.invoke(LocatingElementHandler.java:38)
at com.sun.proxy.$Proxy5.sendKeys(Unknown Source)
at pages.LoginPage.fillUserEmail(LoginPage.java:30)
at tests.LoginTest.logInBase(LoginTest.java:27)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:85)
at org.testng.internal.Invoker.invokeMethod(Invoker.java:659)
at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:845)
at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1153)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:125)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:108)
at org.testng.TestRunner.privateRun(TestRunner.java:771)
at org.testng.TestRunner.run(TestRunner.java:621)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:357)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:352)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:310)
at org.testng.SuiteRunner.run(SuiteRunner.java:259)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1199)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1124)
at org.testng.TestNG.run(TestNG.java:1032)
at org.testng.remote.RemoteTestNG.run(RemoteTestNG.java:111)
at org.testng.remote.RemoteTestNG.initAndRun(RemoteTestNG.java:204)
at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:175)

I know that in LoginPage is no Instanse of driver, but I do not want to create new driver (browser) becouse I want make this tests in one, the same browser.

I was trying use super(driver) but then even tests from GotoLoginPage was fails...

I just want to know what to do to make possible run few testscases in one test using project structure like I use now (pages classes + test classes)

Base Class:

    public class BaseClass {
        public WebDriver driver;

        public BaseClass(WebDriver driver) {
            this.driver = driver;
        }
    }

HomePage:

public HomePage(WebDriver driver){
            super(driver);
        }

LoginPage:

public HomePage(WebDriver driver){
            super(driver);
        }