Given the code fragment: ``java public static void main(String[] args) { String[] arr = {"A", "B", "C", "D", "you"}; List<String> arrList = new ArrayList<>(Arrays.asList(arr)); if (arrList.removeIf(…

Question

public static void main(String[] args) {
 String[] arr = {"A", "B", "C", "D", "you"};
 List<String> arrList = new ArrayList<>(Arrays.asList(arr));
 if (arrList.removeIf( (String s) -> { return s.length() < 2; } )) {
 System.out.println(s + " removed");
 }
}

Options

• AHi removed
• BCompilation fails.
• CAn UnsupportedOperationException is thrown at runtime.
• DThe program compiles, but it prints nothing.

• A
  10% (3)
• B
  81% (25)
• C
  3% (1)
• D
  6% (2)

Explanation

Option B is correct because the variable s is scoped exclusively to the lambda body - it is a parameter of the lambda expression (String s) -> { return s.length() < 2; } and cannot be referenced in the enclosing if block's body where System.out.println(s + " removed") appears. The compiler sees s as undefined in that outer scope and refuses to compile.

Why the distractors fail:

• A ("Hi removed"): Not only does "Hi" not appear in the list, but the code never compiles in the first place.
• C (UnsupportedOperationException): ArrayList fully supports removeIf() - that exception would only apply to unmodifiable collections (e.g., the fixed-size list returned by Arrays.asList() directly, without wrapping it in new ArrayList<>()).
• D (prints nothing): The program never reaches runtime, so it can't silently do nothing - it stops at compile time.

Memory tip: Think of a lambda's parameters like a local variable inside a method - they die when the lambda closes its brace. If you need the removed value outside the lambda, you must capture it in a separate variable before calling removeIf, or use an iterator-based approach instead.

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