DataNG on TestNG

Question

I have tried to use @DataProvider with TestNG and arquillian, but I can't figure it out why it does not work when I use a class that I have created.

If I use it with String, or any primitive datatypes my @Test method successfully receives the DataProvider populated objects.

@DataProvider(name="test")
public Object[][] createdata1() {
    return new Object[] { {"test1"}, {"test2"}, {"test2"} };
}

the above method works, but

@DataProvider(name="test")
public Object[][] createdata1() {
    return new Object[] { {new User("test1")}, {new User("test2")}, {new User("test2")}};
}

does not. This second method gives me null pointers only.

Any ideas?

Answer 1

Return the following instead.

return new Object[][]{
      {new User("test1")},
      {new User("test2")},
      {new User("test2")}};

Better still, If you are using DataProvider often, you can create the following helper method in helper class to help create data easily

public static Object[][] provideData(Object... arObj) {
    Object[][] arObject = new Object[arObj.length][];

    int index = 0;
    for (Object obj : arObj) {
        arObject[index++] = new Object[]{obj};
    }
    return arObject;
}

Hence the following is more easier to decipher ->

@DataProvider(name="test")
public Object[][] createdata1() {
    return provideData(new User("Test1"), new User("Test2"), new User("Test3"));

Answer 2

You have to return an array of arrays, this syntax is motivated by having n-arguments for n-test cases. So the proper syntax would be for returning a User per test.

package testng;

import org.testng.Assert;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;

public class SomeTest {
  @DataProvider(name = "test")
  public Object[][] createdata() {
    return new Object[][] { 
       new Object[] { new User("test1") },
       new Object[] { new User("test2") },
       new Object[] { new User("test2") } };
  }

  @Test(dataProvider = "test")
  public void xxx_happyPath_success(User user) {
    Assert.assertNotNull(user);
  }
}

Answer 3

import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;

public class DataPro {

    @Test(dataProvider = "Sender")  
    public void Receiver(String first, String second)
    {
        System.out.print(first);
        System.out.print(second);
    }

    @DataProvider
    public Object[][] Sender()
    {
        Object[][] data = new Object[2][2];
        data[0][0] = "a";
        data[0][1] = "b";
        data[1][0] = "c";
        data[1][1] = "d";
        return data;
    }

}