Working with Arrays and Collections →easyMultiple SelectObjective-mapped

1Z0-829 Working with Arrays and Collections Practice Question

Which THREE are valid ways to iterate over a Map<String, Integer>?

⚠ Common exam trap

Watch out — candidates often think `Map` itself is iterable (like `Collection`), but it is not; you must use `keySet()`, `values()`, or `entrySet()` to obtain an iterable view, and `forEach` is a default method on `Map` that works directly.

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

✓

for (String key : map.keySet()) { }

`Map.keySet()` returns a `Set<String>` containing all keys, which can be iterated using an enhanced for-each loop. This is a standard way to access keys in a `Map<String, Integer>`.

Answer analysis

Option-by-option breakdown

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

✗
for (Map.Entry<String, Integer> entry : map) { }
Why it's wrong here
Map does not implement Iterable.
✓
for (String key : map.keySet()) { }
Why this is correct
Valid.
✓
map.forEach((k, v) -> { });
Why this is correct
Valid.
✗
for (Integer value : map.values()) { }
Why it's wrong here
Iterates values, not entries.
✓
for (Map.Entry<String, Integer> entry : map.entrySet()) { }
Why this is correct
Valid.

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1Z0-829 Working with Arrays and Collections Practice Question

Why each option matters

Option-by-option breakdown

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