Multiple choice technology programming languages

String[] elements = { “for”, “tea”, “too” }; String first = (elements.length > 0)? elements[0] null; What is the result?

  1. Compilation fails.

  2. An exception is thrown at runtime

  3. The variable first is set to null.

  4. The variable first is set to elements[0].

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The ternary operator checks if elements.length > 0 (true since array has 3 elements), so it returns elements[0] which is 'for'. The colon separates the true and false branches - elements[0] is assigned to first. The array initialization syntax is valid.

AI explanation

To answer this question, we need to understand the conditional (ternary) operator in Java.

The conditional operator (?:) has the following syntax:

(condition) ? expression1 : expression2

If the condition is true, expression1 is evaluated and becomes the result of the entire expression. If the condition is false, expression2 is evaluated and becomes the result.

In the given code snippet:

String first = (elements.length > 0) ? elements[0] : null;

The condition is "elements.length > 0", which checks if the length of the array "elements" is greater than 0.

If the condition is true (i.e., the array has at least one element), the expression "elements[0]" is evaluated and assigned to the variable "first". So, the variable "first" is set to the value of the first element in the array.

If the condition is false (i.e., the array is empty), the expression "null" is evaluated and assigned to the variable "first". So, the variable "first" is set to null.

Therefore, the correct answer is:

D. The variable first is set to elements[0].