Java, TestNG: Why variable initialized in @BeforeTest isn't accessible in second TestClass

Question

everyone! I'm new in autotest and I meet the next problem using Tesng with Java: I have the next structure of my TestProject:

1. abstract public class BasePage - inherited class for page classes PageOne and PageTwo: class BasePage:

abstract public class BasePage {

    public String str;

    public BasePage(){
        System.out.println("Constructor class: BasePage");
    }

    public void doSomething(){
        System.out.println(str);
    }

}

class PageOne:

public class PageOne extends BasePage{

    public PageOne(String strP1){
        this.str = strP1;
        System.out.println("Constructor class: PageOne = " + this.toString());
    }

}

class PageTwo:

public class PageTwo extends BasePage{

    public PageTwo(String strP2){
        this.str = strP2;
        System.out.println("Constructor class: PageTwo = " + this.toString());
    }


}

2. abstract public class BaseTest - inherited class for test classes TestOne and TestTwo: class BaseTest:

abstract public class BaseTest {

    PageOne p1;
    PageTwo p2;

    @BeforeTest
    public void setUp(){
        System.out.println("BEFORE TEST in BaseTest: create p1 and p2");
        p1 = new PageOne();
        p2 = new PageTwo();
                System.out.println("***** BEFORE *****");
    }

class TestOne:

public class TestOne extends BaseTest{

    public TestOne(){
        System.out.println("Constructor class: TestOne");
    }
    @Test
    public void testDoSomething(){
        p1.doSomething();
        p2.doSomething();

    }

}

class TestTwo:

public class TestTwo extends BaseTest{

    public TestTwo(){
        System.out.println("Constructor class: TestTwo");
    }

    @Test
    public void testDoSomething(){
        p1.doSomething();
        p2.doSomething();
    }

}

3. my testng.xml is:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd">
<suite name="All Test Suite">
    <test verbose="2" preserve-order="true" name="test1">
        <classes>
            <class name="org.example.tests.TestOne"/>
            <class name="org.example.tests.TestTwo"/>
        </classes>
    </test>
</suite>

But when I started my testng.xml I got error:

java.lang.NullPointerException: Cannot invoke "org.example.pages.PageOne.doSomething()" because "this.p1" is null and my system.outs:

Constructor class: TestOne
Constructor class: TestTwo
BEFORE TEST in BaseTest: create p1 and p2
Constructor class: BasePage
Constructor class: PageOne = org.example.pages.PageOne@6a400542
Constructor class: BasePage
Constructor class: PageTwo = org.example.pages.PageTwo@7e0b85f9
***** BEFORE TEST END *****
strP1
strP2
***** AFTER CLASS *****
java.lang.NullPointerException: Cannot invoke "org.example.pages.PageOne.doSomething()" because "this.p1" is null

SO the second test TestTwo is failed because there are no more page variable p1. I can solve this problem by using annotation @BeforeClass or @BeforeMethod. But I can't understand why it doesn't work with @BeforeTest. Could anybody explain it, please!

Answer 1

The solution is to set variables static PageOne p1; PageTwo p2; I found detailed explanation here http://makeseleniumeasy.com/2020/08/09/are-you-getting-nullpointerexception-for-second-testng-test-while-running-as-a-suite/