Java MCQ Questions - Operators & Assignments
This section focuses on the "operators and assignments" in Java programming. These Multiple Choice Questions (MCQ) should be practiced to improve the Java programming skills required for various interviews (campus interviews, walk-in interviews, company interviews), placements and other competitive examinations.
1. Which of the following can be operands of arithmetic operators?
A. Characters
B. Boolean
C. Numeric
D. Both Numeric & Characters
View Answer
Ans : D
Explanation: The operand of arithmetic operators can be any of numeric or character type, But not boolean.
2. Modulus operator, %, can be applied to which of these?
A. Both Integers and floating - point numbers
B. Integers
C. Floating - point numbers
D. None of the mentioned
View Answer
Ans : A
Explanation: Modulus operator can be applied to both integers and floating point numbers..
3. Decrement operator, −−, decreases the value of variable by what number?
A. 1
B. 2
C. 3
D. 4
View Answer
Ans : A
Explanation: Decrement operator, −−, decreases the value of variable by 1.
4. Which of these statements are incorrect?
A. Assignment operators can be used only with numeric and character data type
B. Assignment operators are more efficiently implemented by Java run-time system than their equivalent long forms
C. Assignment operators run faster than their equivalent long forms
D. None of the mentioned
View Answer
Ans : D
Explanation: None of the mentioned.
5. Can 8 byte long data type be automatically type cast to 4 byte float data type?
A. TRUE
B. FALSE
C. Can be true or false
D. can not say
View Answer
Ans : A
Explanation: Both data types have different memory representation that is why 8-byte integral data type can be stored to 4-byte floating point data type.
6. Evaluate the value of the expression?
6 - 2 + 10 % 4 + 7
A. 14
B. 12
C. 13
D. 10
View Answer
Ans : C
Explanation: Output of the expression is 13.
7. What is/are highest order precedence operator(s) in Java?
A. ( )
B. { }
C. Both A & B
D. None of these
View Answer
Ans : C
Explanation: Parentheses(), Array subscript{} and Member selection- have the same precedence.
8. The && and || operators
A. Compare two boolean values
B. Compare two numeric values
C. Combine two boolean values
D. Combine two numeric values
View Answer
Ans : C
Explanation: Logical AND(&&) and Logical OR(||) combine two boolean values.
9. Which of the following is the correct expression that evaluates to true if the number x is between 1 and 100 or the number is negative?
A. ((x < 100) && (x > 1)) && (x < 0)
B. ((x < 100) && (x > 1)) || (x < 0)
C. (1 > x > 100) || (x < 0)
D. 1 < x < 100 || x < 0
View Answer
Ans : B
Explanation: No explanation.
10. Select from among the following character escape code which is not available in Java.
A. \\
B. \v
C. \a
D. \t
View Answer
Ans : C
Explanation: No explanation.
11. What will be the output of the program?
class Main {
public static void main(String [] args)
{
Main p = new Main();
p.start();
}
void start()
{
long [] a1 = {3,4,5};
long [] a2 = fix(a1);
System.out.print(a1[0] + a1[1] + a1[2] + " ");
System.out.println(a2[0] + a2[1] + a2[2]);
}
long [] fix(long [] a3)
{
a3[1] = 7;
return a3;
}
}
A. 12 15
B. 15 15
C. 3 7 5 3 7 5
D. 3 4 5 3 7 5
View Answer
Ans : B
Explanation: The reference variables a1 and a3 refer to the same long array object. When the [1] element is updated in the fix() method, it is updating the array referred to by a1. The reference variable a2 refers to the same array object.
So Output: 3+7+5+"" ""3+7+5
Output: 15 15 Because Numeric values will be added
12. What will be the output of the program?
class Main {
public static void main(String [] args)
{
Main p = new Main();
p.start();
}
void start()
{
boolean b1 = false;
boolean b2 = fix(b1);
System.out.println(b1 + " " + b2);
}
boolean fix(boolean b1)
{
b1 = true;
return b1;
}
}
A. true true
B. true false
C. false true
D. false false
View Answer
Ans : C
Explanation: The boolean b1 in the fix() method is a different boolean than the b1 in the start() method. The b1 in the start() method is not updated by the fix() method.
13. What will be the output of the program?
class Main {
public static void main(String [] args)
{
Main p = new Main();
p.start();
}
void start()
{
String s1 = "s";
String s2 = fix(s1);
System.out.println(s1 + " " + s2);
}
String fix(String s1)
{
s1 = s1 + "st";
System.out.print(s1 + " ");
return "st";
}
}
A. s st
B. sst st
C. st s st
D. sst s st
View Answer
Ans : D
Explanation: When the fix() method is first entered, start()'s s1 and fix()'s s1 reference variables both refer to the same String object (with a value of ""s""). Fix()'s s1 is reassigned to a new object that is created when the concatenation occurs (this second String object has a value of ""sst""). When the program returns to start(), another String object is created, referred to by s2 and with a value of ""st"".
14. Which of the following will produce an answer that is closest in value to a double, d, while not being greater than d?
A. (int)Math.min(d);
B. (int)Math.abs(d);
C. (int)Math.max(d);
D. (int)Math.floor(d);
View Answer
Ans : D
Explanation: The casting to an int is a smokescreen.
15. Predict the output of following Java Program?
class Test {
public static void main(String args[]) {
int x = -4;
System.out.println(x>>1);
int y = 4;
System.out.println(y>>1);
}
}
A. Compiler Error: Operator >> cannot be applied to negative numbers
B. -2
2
C. 2
D. 2
2
View Answer
Ans : B
Explanation: No explantion.
16. With x = 0, which of the following are legal lines of Java code for changing the value of x to 1?
1. x++;
2. x = x + 1;
3. x += 1;
4. x =+ 1;
A. 1, 2 & 3
B. 1 & 4
C. 1, 2, 3 & 4
D. 3 & 2
View Answer
Ans : C
Explanation: Operator ++ increases value of variable by 1. x = x + 1 can also be written in shorthand form as x += 1. Also x =+ 1 will set the value of x to 1.
17. What is the output of this program?
class Main {
public static void main(String args[])
{
double var1 = 2 + 4;
double var2 = var1 / 4;
int var3 = 2 + 4;
int var4 = var3 / 4;
System.out.print(var2 + " " + var4);
}
}
A. 0 1
B. 1 1
C. 1.5 1
D. 1.5 1.0
View Answer
Ans : C
Explanation: No Explanation.
18. What will be the output of the program?
class Main {
public static void main(String [] args)
{
int x=20;
String sup = (x < 15) ? "s" : (x < 22)? "t" : "h";
System.out.println(sup);
}
}
A. s
B. t
C. h
D. Compilation fails
View Answer
Ans : B
Explanation: This is an example of a nested ternary operator. The second evaluation (x < 22) is true, so the ""t"" value is assigned to sup.
19. What will be the output of the program?
class Bitwise
{
public static void main(String [] args)
{
int x = 11 & 9;
int y = x ^ 3;
System.out.println( y | 12 );
}
}
A. 7
B. 0
C. 14
D. 8
View Answer
Ans : C
Explanation: The & operator produces a 1 bit when both bits are 1. The result of the & operation is 9. The ^ operator produces a 1 bit when exactly one bit is 1; the result of this operation is 10. The | operator produces a 1 bit when at least one bit is 1; the result of this operation is 14.
20. What is the output of this program?
class increment
{
public static void main(String args[])
{
int g = 5;
System.out.print(++g * 8);
}
}
A. 44
B. 56
C. 48
D. 40
View Answer
Ans : C
Explanation: Operator ++ has more preference than *, thus g becomes 4 and when multiplied by 8 gives 32.
21. What is the output of relational operators?
A. Integer
B. Boolean
C. Characters
D. Double
View Answer
Ans : B
Explanation: None.
22. Which of these is returned by "greater than", "less than" and "equal to" operators?
A. Integers
B. Floating - point numbers
C. Boolean
D. None of the mentioned
View Answer
Ans : C
Explanation: All relational operators return a boolean value ie. true and false.
23. Which of the following operators can operate on a boolean variable?
A. &&
B. ==
C. ?:
D. +=
View Answer
Ans : D
Explanation: Operator Short circuit AND, &&, equal to, == , ternary if-then-else, ?:, are boolean logical operators. += is an arithmetic operator it can operate only on numeric values.
24. Which of these operators can skip evaluating right hand operand?
A. !
B. |
C. &
D. &&
View Answer
Ans : D
Explanation: Operator short circuit and, &&, and short circuit or, ||, skip evaluating right hand operand when output can be determined by left operand alone.
25. Which of these statements is correct?
A. true and false are numeric values 1 and 0
B. true and false are numeric values 0 and 1
C. true is any non zero value and false is 0
D. true and false are non numeric values
View Answer
Ans : D
Explanation: True and false are keywords, they are non numeric values which do not relate to zero or non zero numbers. true and false are boolean values.
26. What is the output of this program?
class Relational_operator
{
public static void main(String args[])
{
int var1 = 5;
int var2 = 6;
System.out.print(var1 > var2);
}
}
A. 1
B. 0
C. TRUE
D. FALSE
View Answer
Ans : D
Explanation: Operator > returns a boolean value. 5 is not greater than 6 therefore false is returned.
output:
$ javac Relational_operator.java
$ java Relational_operator
false
27. What is the output of this program?
class ternary_operator
{
public static void main(String args[])
{
int x = 3;
int y = ~ x;
int z;
z = x > y ? x : y;
System.out.print(z);
}
}
A. 0
B. 1
C. 3
D. -4
View Answer
Ans : C
Explanation: None.
output:
$ javac ternary_operator.java
$ java ternary_operator
3
28. What is the output of this program?
class Output
{
public static void main(String args[])
{
int x , y = 1;
x = 10;
if (x != 10 && x / 0 == 0)
System.out.println(y);
else
System.out.println(++y);
}
}
A. 1
B. 2
C. Runtime error owing to division by zero in if condition
D. Unpredictable behavior of program
View Answer
Ans : B
Explanation: Operator short circuit and, &&, skips evaluating right hand operand if left hand operand is false thus division by zero in if condition does not give an error.
output:
$ javac Output.java
$ java Output
2
29. What is the output of this program?
class Output
{
public static void main(String args[])
{
boolean a = true;
boolean b = false;
boolean c = a ^ b;
System.out.println(!c);
}
}
A. 0
B. 1
C. FALSE
D. TRUE
View Answer
Ans : C
Explanation: None.
output:
$ javac Output.java
$ java Output
false
30. Which of these have highest precedence?
A. ()
B. ++
C. *
D. >>
View Answer
Ans : A
Explanation: Order of precedence is (highest to lowest) a -> b -> c -> d.
31. What should be expression1 evaluate to in using ternary operator as in this line?
expression1 ? expression2 : expression3
A. Integer
B. Floating - point numbers
C. Boolean
D. None of the mentioned
View Answer
Ans : C
Explanation: The controlling condition of ternary operator must evaluate to boolean.
32. What is the value stored in x in following lines of code?
int x, y, z;
x = 0;
y = 1;
x = y = z = 8;
A. 0
B. 1
C. 9
D. 8
View Answer
Ans : D
Explanation: None.
33. What is the order of precedence (highest to lowest) of following operators?
1. &
2. ^
3. ?:
A. 1 -> 2 -> 3
B. 2 -> 1 -> 3
C. 3 -> 2 -> 1
D. 2 -> 3 -> 1
View Answer
Ans : A
Explanation: None.
34. What is the output of this program?
class operators
{
public static void main(String args[])
{
int var1 = 5;
int var2 = 6;
int var3;
var3 = ++ var2 * var1 / var2 + var2;
System.out.print(var3);
}
}
A. 10
B. 11
C. 12
D. 56
View Answer
Ans : C
Explanation: Operator ++ has the highest precedence than / , * and +. var2 is incremented to 7 and then used in expression, var3 = 7 * 5 / 7 + 7, gives 12.
output:
$ javac operators.java
$ java operators
12
35. What is the output of this program?
class Main
{
public static void main(String args[])
{
int x = 8;
System.out.println(++x * 3 + " " + x);
}
}
A. 24 8
B. 24 9
C. 27 8
D. 27 9
View Answer
Ans : D
Explanation: Operator ++ has higher precedence than multiplication operator, *, x is incremented to 9 than multiplied with 3 giving 27.
output:
$ javac operators.java
$ java operators
27 9
Also check :
Discussion