# Quiz 1: Foundations

• Define "object" (1/12)

• What is wrong with the following code? Explain. Fix it. (1/12)

if (s.isBlank() || s == null)
{
    throw new IllegalArgumentException("no string!");
}

Solution: If s is null, it won't have the isBlank method. Fix: if (s==null || s.isBlank())

• Create a Main class with the main() method and print out the third argument. (2/12)

Solution:

public class Main
{
    public static void main(final String[] args)
    {
        System.out.println(args[2]);
    }
}

• What does final mean? ive an example of a field that should be final for a Person class. (2/12)

Solution: Means the variable can only be assigned once. It's a compile error if you try to assign it the 2nd time. Example: a Person's date of birth.

• Create a Restaurant class with two well-named instance variables: nationality (e.g. Italian), opening and closing hours (use a 24-hour clock), getters and setters as appropriate, and a constructor. With JavaDoc comments. Use proper validation techniques.