Working with Streams and Lambda Expressions →mediumMultiple SelectObjective-mapped

1Z0-829 Working with Streams and Lambda Expressions Practice Question

Which THREE of the following are valid ways to create a Stream<String>? (Choose three.)

⚠ Common exam trap

It's easy for candidates to confuse `chars()` as returning a `Stream<Character>` or `Stream<String>`, when in fact it returns an `IntStream` of code points, and they may also mistakenly think `Stream` can be instantiated with `new` like a regular class.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Arrays.stream(new String[]{"a", "b"})

`Arrays.stream(T[])` returns a `Stream<T>` from an array. Passing `new String[]{"a", "b"}` creates a `Stream<String>` directly, as the method is overloaded for object arrays.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✓
Arrays.stream(new String[]{"a", "b"})
Why this is correct
Arrays.stream for object arrays returns a Stream of the array elements.
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Stream.of("a", "b")
Why this is correct
Stream.of with varargs creates a stream of the provided elements.
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List.of("a", "b").stream()
Why this is correct
Collection.stream() is a standard way to obtain a stream.
✗
"ab".chars()
Why it's wrong here
chars() returns an IntStream (primitive), not a Stream<String>.
✗
new Stream<String>()
Why it's wrong here
Stream is an interface; cannot be instantiated directly.

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1Z0-829 Working with Streams and Lambda Expressions Practice Question

Why each option matters

Option-by-option breakdown

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