1Z0-811 Java Language Fundamentals 5

Question 1

Which of the following is true about local variables in Java?

Accepted Answer

They must be explicitly initialized before use

Answer

Local variables have no default value in Java; the compiler raises an error if you use one before initializing it.

Question 2

What is the output of the following?

int[] arr = {5, 10, 15};
System.out.println(arr.length);

Accepted Answer

3

Answer

The array has three elements (5, 10, 15), so arr.length returns 3.

Question 3

Which of the following correctly describes a labeled break statement?

Accepted Answer

It breaks from a specified outer loop

Answer

A labeled break exits the loop (or block) associated with the specified label, not just the innermost one.

Question 4

What does the following evaluate to?

10 == 10.0

Accepted Answer

true, after numeric promotion

Answer

Java promotes the int 10 to double 10.0 before comparison, so 10 == 10.0 evaluates to true.

Question 5

Which of the following is true about the 'static' keyword on a variable?

Accepted Answer

It creates a class-level variable shared by all instances

Answer

A static variable belongs to the class rather than any instance; all objects share the same copy.

(1Z0-811) Oracle Java SE11 Programmer Practice Test