Java Generics Value.<SomeValue>

Question

I had an interview test and saw the following code:

EDIT:

public class TestValue {
    private Value<SomeValue> defaultValue;

    @Test
    public void Empty_Value_Has_No_Value() {
        Assert.assertFalse(Value.<SomeValue> createEmptyValue()
            .hasValue());
    }

    @Test
    public void Default_Value_IsEmpty() {
        Assert.assertEquals(Value.<SomeValue> createEmptyValue(),
            defaultValue);
    }

    @Test
    public void Non_Empty_Value_Has_Value() {
        Assert.assertTrue(new Value<SomeValue>(true, new SomeValue())
            .hasValue());
    }
}

I had never seen Java generic like

Value.<SomeValue>

The test is to implement Value class with the given unit test code above.

I tried to figure out the Value method signature below (need implementation):

public interface Value<T> {

    public boolean hasValue();
    public Value<T> createEmptyValue();
}

Any one know, please help?

Thank you

EDIT: Should be like this according to answers below @marlon

public class Value<T> {

    public boolean hasValue(){}
    public static <M> Value<M> createEmptyValue(){}; //need <M>
}

The key syntax to know:

Value.<SomeValue>  //ClassName.<Type>method

is way to invoke static method of a class with parameterized argument.

EDIT: according to @snipes83, syntax to invoke non-static method of a class with parameterized argument.

SomeObject.<Type>method

Answer 1

Value.<SomeValue> it's the way generics are represented for methods.

Using Google Guava's Optional as an example:

Optional<String> email = Optional.<String>of(strEmail);

See Generic Types - Invoking generic methods

Since interfaces cannot declare static methods (shame on you java), just declare your method as static and forget about the interface, like this:

class Value<T> {

    public static <T> Value<T> createEmptyValue(){
        return null;
    }
}