1Z0-811 Timed Practice Test 1 — 10 Questions

Question 1

Arrange the steps to compile and run a Java program from the command line in the correct order.

Question 2

Arrange the steps to handle an exception using try-catch-finally in Java in the correct order.

Question 3

Arrange the steps to use the Scanner class to read user input in Java in the correct order.

Question 4

Arrange the steps to create an object from a class in Java in the correct order.

Question 5

Arrange the steps to use a for loop to iterate over an array in Java in the correct order.

Question 6

Arrange the steps to overload a method in Java in the correct order.

Question 7

A developer writes: boolean b = !true && false; What is the value of b?

Accepted Answer

false. The expression `!true && false` is evaluated as `(!true) && false`, which is `false && false`. The logical AND (`&&`) operator returns `true` only if both operands are `true`; otherwise, it returns `false`. Therefore, `b` is assigned `false`. Option B is correct.

Answer

Compilation error: invalid operator.

Answer

NullPointerException

Answer

true

Question 8

A developer writes: int x; System.out.println(x); What is the result?

Accepted Answer

Compilation fails. Local variables must be initialized before use. x is not initialized, so compilation fails.

Answer

null

Answer

Runtime error

Answer

0

Question 9

A junior developer wrote the following code to compare two strings entered by a user: if (username == "admin") { grantAccess(); } else { denyAccess(); }. The code always denies access even when the user enters 'admin'. What is the most likely cause, and how should the code be fixed?

Accepted Answer

The strings are compared using == which checks reference equality. Use username.equals("admin") instead.. The == operator compares object references, not content. String literals may be interned, but dynamically entered strings are not guaranteed to be interned. The correct fix is to use equals() method.

Answer

The input string has leading or trailing spaces. Use username.trim().equals("admin") instead.

Answer

The variable username is null, causing a NullPointerException that is caught and denied access. Add a null check.

Answer

The strings are compared using == which is case-sensitive. Use username.equalsIgnoreCase("admin") instead.

Question 10

Given: int a = 10; int b = 20; boolean flag = a++ > 10 && ++b > 20; What are the values of a and b after execution?

Accepted Answer

a=11, b=20. The expression `a++ > 10 && ++b > 20` uses short-circuit evaluation. Since `a++` is post-increment, the comparison uses the original value of `a` (10) before incrementing, so `10 > 10` is false. Because the left operand is false, the `&&` operator short-circuits and the right operand `++b > 20` is never evaluated. Therefore, `a` is incremented to 11, but `b` remains 20, making option D correct.

Answer

a=10, b=21

Answer

a=10, b=20

Answer

a=11, b=21