//will work as expected
        //both Person() and Person(var, var,var) are defined functions of the class Person
        Person testP = new Person("Name", "Nachname", "mail@mail.com");
        testP.setEmail("mail2@mail.com");
        data.add(testP);

        //will fail horribly
        Person testP2 = new Person();
            testP2.setEmail("mail2@mail.com");
            testP2.setFirstName("Michael");
            testP2.setLastName("Sloawiks");
        data.add(testP2);