How to test method which uses Random() but can't pick the same number twice

I'm creating a little java game which randomly picks from a list of Primitive data (using Random().nextInt()) types and asks which type is larger (or if they're both the same). I've also made it so that if the same Primitive data type is picked then random.nextInt() is called again to ensure the selections are different.

My trouble now comes in testing that the code works. Below is the Game.class:

static final PrimitiveDataType BOOLEAN_TYPE = new PrimitiveDataType("boolean", 0);
    static final PrimitiveDataType BYTE_TYPE = new PrimitiveDataType("byte", 8);
    static final PrimitiveDataType SHORT_TYPE = new PrimitiveDataType("short", 16);
    static final PrimitiveDataType CHAR_TYPE = new PrimitiveDataType("char", 16);
    static final PrimitiveDataType INT_TYPE = new PrimitiveDataType("int", 32);
    static final PrimitiveDataType LONG_TYPE = new PrimitiveDataType("long", 64);
    static final PrimitiveDataType FLOAT_TYPE = new PrimitiveDataType("float", 32);
    static final PrimitiveDataType DOUBLE_TYPE = new PrimitiveDataType("double", 64);
static List<PrimitiveDataType> PRIMITIVE_TYPES = Arrays.asList(BOOLEAN_TYPE, BYTE_TYPE, SHORT_TYPE, CHAR_TYPE,
        INT_TYPE, LONG_TYPE, FLOAT_TYPE, DOUBLE_TYPE);

static List<PrimitiveDataType> chosenDataTypes = new ArrayList<PrimitiveDataType>();

private static int numberOfQuestions; 

static Random numberGenerator = new Random();

static void setChosenDataTypeIndexs(Random numberGenerator) {




    int choice1 =  numberGenerator.nextInt(PRIMITIVE_TYPES.size()-1)+0;
    int choice2 =  numberGenerator.nextInt(PRIMITIVE_TYPES.size()-1)+0;

    System.out.println("Random Roll (1) " +choice1);
    System.out.println("Random Roll (2) " +choice2);
    do {

        choice2 = numberGenerator.nextInt(PRIMITIVE_TYPES.size()-1)+0;

    } while (choice1==choice2);

    Game.chosenDataTypes.add(PRIMITIVE_TYPES.get(choice1));
    Game.chosenDataTypes.add(PRIMITIVE_TYPES.get(choice2));

}

static PrimitiveDataType getChosenDataTypeIndexs(int i) {
    return chosenDataTypes.get(i);
}

public static void setNumberOfQuestions(int i) {

    numberOfQuestions = i;

}

I've had a go with writing a testclass with Mockito, but i'm not sure if i'm mocking correctly due to getting passing test with the dice roll outputting the same number. Also, if i mock out the output of Random.nextInt() to a specific wouldn't this create an infinite loop as it looks for a different number?

public class GameTest {





@Test
public void getChosenDataTypesTest(){


    Random randomNumberMock = Mockito .mock(Random.class);
    when(randomNumberMock.nextInt()).thenReturn(1);

    Game.setChosenDataTypeIndexs(randomNumberMock);

    assertNotEquals(Game.chosenDataTypes.get(0), Game.chosenDataTypes.get(1));

    verify(randomNumberMock,times(2)).nextInt();




}
@Test
public void setNumberOfQuestionsTest(){




    Game.setNumberOfQuestions(1);

    assertEquals(1,Game.getNumberOfQuestions());


}