1Z0-811 Timed Practice Test 2 — 10 Questions

Question 1

What is the value of the expression (10 > 5) && (3 < 2)?

Accepted Answer

false. The expression (10 > 5) evaluates to true, and (3 < 2) evaluates to false. The logical AND operator (&&) returns true only if both operands are true. Since one operand is false, the entire expression evaluates to false. In Java, the result of a boolean expression is a boolean literal, not an integer.

Answer

1

Answer

true

Answer

0

Question 2

Which primitive data type should be used to store a single character?

Accepted Answer

char. Option C is correct because the `char` primitive data type in Java is specifically designed to store a single 16-bit Unicode character, ranging from '\u0000' (0) to '\uffff' (65,535). It can represent any character in the Unicode standard, including letters, digits, and symbols, making it the appropriate choice for a single character value.

Answer

int

Answer

byte

Answer

String

Question 3

A developer writes: for(int i=0; i<10; i++) { if(i%2==0) continue; System.out.print(i); }. What is the output?

Accepted Answer

13579. The loop iterates from i=0 to i=9. The `continue` statement skips the rest of the loop body when the condition `i%2==0` is true (i.e., when i is even). Therefore, only odd values of i (1, 3, 5, 7, 9) are printed, producing the output '13579'. Option B is correct.

Answer

0123456789

Answer

02468

Answer

123456789

Question 4

What is the result of: System.out.println(10 + 20 + "30");

Accepted Answer

3030. In Java, the '+' operator is left-associative. The expression `10 + 20 + "30"` is evaluated as `(10 + 20) + "30"`, which first performs integer addition to get `30`, then concatenates that integer with the string `"30"`, resulting in the string `"3030"`. The `System.out.println` method then prints the string `3030`.

Answer

102030

Answer

30

Answer

Compilation fails

Question 5

What is the output of the following code? int[] a = {1,2,3}; int[] b = a; b[0] = 99; System.out.println(a[0]);

Accepted Answer

99. Option C is correct because in Java, arrays are reference types. When `int[] b = a;` is executed, `b` does not create a new array; it simply references the same array object as `a`. Therefore, modifying `b[0]` directly changes the element in the original array `a`, so `a[0]` prints 99.

Answer

0

Answer

1

Answer

Compilation error

Question 6

Which TWO statements are true about interfaces in Java?

Accepted Answer

Interfaces can contain private methods.. Option A is correct because, since Java 9, interfaces can contain private methods to share common code between default methods or static methods within the interface, without exposing that logic to implementing classes. Option D is correct because all variables declared in an interface are implicitly public, static, and final, meaning they are constants that cannot be changed once assigned.

Answer

Interfaces can be instantiated.

Answer

Interfaces can contain constructors.

Answer

Interfaces cannot have default methods.

Question 7

Given: abstract class Shape { abstract void draw(); } class Circle extends Shape { void draw() {} } Which is true?

Accepted Answer

Circle must override draw(). Option B is correct because Circle is a concrete class that extends the abstract class Shape, which declares the abstract method draw(). A concrete subclass of an abstract class must provide an implementation for all inherited abstract methods, unless the subclass is also declared abstract. Circle provides an implementation of draw() with an empty body, which satisfies the override requirement.

Answer

Shape cannot have a constructor

Answer

Shape s = new Shape(); is valid

Answer

draw() must be public in Circle

Question 8

A method throws a checked exception. Which of the following is the correct way to handle it in the calling method?

Accepted Answer

Enclose the call in a try-catch block.. Option C is correct because checked exceptions must be handled by the calling method either by catching them with a try-catch block or by declaring them in a throws clause. Since the question asks for the correct way to handle it, enclosing the call in a try-catch block is a valid and direct handling approach that prevents the exception from propagating unhandled.

Answer

Ignore the exception since it is checked.

Answer

Add a throws clause to the calling method.

Answer

Use a finally block without catch.

Question 9

Given: int a = 9; int b = 2; double c = a / b; System.out.println(c); What is the output?

Accepted Answer

4.0. Integer division truncates decimal part, so 9/2 = 4, then assigned to double gives 4.0.

Answer

4.5

Answer

4.0

Answer

4