Quiz 2.4: Question types and code

Question 1

Which keyword limits a field to its own class?

1. public
2. private
3. protected
4. final

Show correct answer

private

Show hint

Think of access modifiers.

Question 2

Which statements about this Java code are true?

List<String> names = List.of("Ada", "Linus");
names.add("Grace");

1. List.of returns an immutable list
2. The add call throws an exception
3. The list ends up with three names
4. List<String> is not valid Java syntax

Show correct answer

List.of returns an immutable list

The add call throws an exception

Question 3

Which method returns the larger of two numbers?

1. This one:

   int max(int a, int b) {
       return a < b ? a : b;
   }

2. This one:

   int max(int a, int b) {
       return a > b ? a : b;
   }

Show correct answer

This one:

int max(int a, int b) {
    return a > b ? a : b;
}

Question 4

Which React component shows the count after a click?

1. This one:

   function Counter() {
     const [count, setCount] = useState(0);
     return <button onClick={() => count + 1}>{count.toString()}</button>;
   }

2. This one:

   function Counter() {
     const [count, setCount] = useState(0);
     return <button onClick={() => setCount(count + 1)}>{count}</button>;
   }

Show correct answer

This one:

function Counter() {
  const [count, setCount] = useState(0);
  return <button onClick={() => setCount(count + 1)}>{count}</button>;
}

Question 5

Name the HTTP method that creates a resource in a REST API.

Show correct answer

POST

Show hint

It is one word in capitals.