Java Switch Case Interview MCQ Questions and Answers
1) A SWITCH case statement in Java is a ___ control statement.
A) Iteration
B) Loop
C) Selection
D) Jump
Answer [=]
C
2) Which is the alternative to SWITCH in Java language?
A) break, continue
B) for, while
C) if, else
D) goto, exit
Answer [=]
C
Explanation:
We can implement a SWITCH statement using IF, ELSE IF and ELSE control statements.
3) What are the keywords used to implement a SWITCH case in Java language?
A) switch, case
B) default
C) break
D) All
Answer [=]
D
4) What are the parts of a SWITCH in java?
A) switch input condition
B) case constants
C) case statements
D) All
Answer [=]
D
5) A SWITCH statement accepts ___ type of data as input.
A) byte
B) short
C) int
D) All
Answer [=]
D
6) A switch statement in Java accepts ___ as input data.
A) enum
B) String
C) enum and String
D) long
Answer [=]
C
Explanation:
SWITCH does not support long constants.
7) Choose the correct syntax of SWITCH statement in Java below.
A) switch(input)
{
case constant1: //statements; break;
case constant2: //statements; break;
default: //statements;
};
B ) switch(input)
{
case constant1: //statements; break;
case constant2: //statements; break;
default: //statements;
}
C) switch(input)
{
case constant1: //statements; break;
case constant2: //statements; break;
default case: //statements;
};
D) switch(input)
{
case constant1: //statements; break;
case constant2: //statements; break;
default case: //statements;
}
Answer [=] B
Explanation: The semicolon (;) after SWITCH {} is not required. So option A is wrong though it compiles fine.
8) Which version of Java did start supporting String as the input data type of a SWITCH?
A) JDK 5
B) JDK 6
C) JDK 7
D) JDK 8
Answer [=] C
9) What is the output of Java program with SWITCH below?
int a=10;
switch(a)
{
case 10: System.out.println("TEN");
}
A) No output
B) TEN
C) Compiler error as there is no BREAK.
D) None
Answer [=] B
Explanation: "break;" is optional.
10) What is the output of the Java program below?
int b=20;
switch(b)
{
default: System.out.println("LION");
}
A) No output
B) LION
C) Compiler error as there are no CASE statements.
D) None
Answer [=] B
Explanation: DEFAULT statement alone can be written without any error.
11) What is the output of the Java program below?
String animal = "GOAT";
switch(animal)
{
break: System.out.println("DOMESTIC");
}
A) No output
B) GOAT
C) DOMESTIC
D) Compiler error
Answer [=] D
Explanation: Case statements should start with either "case" or "default" only.
12) What is the output of the Java program below?
String college = "OXFORD";
switch("STANFORD")
{
case college: System.out.println("EXAM TIME"); break;
default: System.out.println("UNKNOWN");
}
A) EXAM TIME
B) UNKNOWN
C) STANFORD
D) Compiler error
Answer [=]D Explanation: case expressions must be constant expressions. So, make the variable final.
final String college = "OXFORD";
13) What is the output of Java program with SWITCH?
int num=20;
switch(num)
{
case 10: System.out.println("TEN"); break;
case 20: System.out.println("TWENTY"); break;
case 30: System.out.println("THIRTY");
}
A) TEN
B) TWENTY
C) THIRTY
D) TEN TWENTY
Answer [=] B
14) What is the output of Java program below?
int num=40;
switch(num)
{
case 5: System.out.println("FIVE"); break;
case 35+5: System.out.println("FORTY"); break;
case 20+30: System.out.println("FIFTY");
}
A) FIVE
B) FORTY
C) FIFTY
D) Compiler error
Answer [=]B
Explanation:It is allowed to write expressions that result in constant values.
15) What is the output of the below Java program?
int persons = 45;
int random = 45;
switch(random)
{
case persons: System.out.print("CRICKET ");
default: System.out.println("RUGBY");
}
A) CRICKET
B) CRICKET RUGBY
C) RUGBY
D) Compiler error
Answer [=]D
Explanation:Error: case expressions must be constant expressions So, make the variable final.
final int persons = 45;
//Then, output will be
CRICKET
16) What is the output of the below Java program?
switch(15)
{
case 5*2: System.out.println("TEN");break;
case 5*4-5:System.out.println("FIFTEEN");break;
case 60/4+5: System.out.println("TWENTY");
}
A) TEN
B) FIFTEEN
C) TWENTY
D) Compiler error
Answer [=] B
Explanation: Any expression that results in a Constant can be used as a "case constant".
17) A SWITCH fall through occurs in Java only in the absence of ___.
A) case keyword
B) break keyword
C) default keyword
D) None
Answer [=] B
8) What is the purpose of designing a SWITCH logic with a fall-through in Java?
A) To define ranges.
B) To define additions
C) To improve switch block performance
D) None
Answer [=] A
19) Does the following Java code-snippet compile?
switch(45)
{
case 10: ;
}
A) NO
B) YES
C) -
D) -
Answer [=]
B
Explanation:
You can specify dummy statements in java using a Semicolon (;).
20) What is the output of the below Java program with a SWITCH statement?
int points=6;
switch(points)
{
case 6: ;
case 7: System.out.println("PASS");break;
case 8: ;
case 9: System.out.println("Excellent");break;
case 10: System.out.println("Outstanding"); break;
default: System.out.println("FAIL");
}
A) PASS
B) Excellent
C) Outstanding
D) FAIL
Answer [=]A
Explanation:This is the way we define ranges in a SWITCH construct.
21) Choose TRUE or FALSE. A SWITCH can be used to compare values for high or low.
A) FALSE
B) TRUE
C) -
D) -
Answer [=]A
Explanation: More or Less conditions can not be checked with a SWITCH statement in Java.
22) State TRUE or FALSE. It is allowed to use duplicate case constants inside a Java SWITCH statement.
A) FALSE
B) TRUE
C) -
D) -
Answer [=] A
Explanation:SWITCH case constants must be unique.
23) State TRUE or FALSE. SWITCH works faster than the IF-ELSE ladder in Java.
A) FALSE
B) TRUE
C) -
D) -
Answer [=] B
Explanation: The compiler (JIT-Just In Time) creates a JUMP-TABLE for switch case branchings. So, it does not take time during Runtime. So, the SWITCH statement is fast.
24) Choose the correct statement about Java SWITCH statements.
A) A SWITCH can contain another SWITCH statement.
B) Switch case statements are allowed inside IF-ELSE ladders.
C) Switch statements are allowed inside Loops like for, while and do while.
D) All
Answer [=] D
25) What is the output of the below Java program?
int hours = 10;
switch(hours)
{
case 10: System.out.println("TEN");break;
case 10: System.out.println("TEN AGAIN"); break;
default: System.out.println("TEN AS USUAL");
}
A) TEN
B) TEN AGAIN
C) TEN AS USUAL
D) Compiler error
Answer [=] D
Explanation: Case constant 10 is duplicate. So, it causes compiler error.
26) What is the output of the below Java program?
char grade = 'B';
switch(grade)
{
case 'A': System.out.print("GRADE-A ");break;
case 'B': System.out.print("GRADE-B ");
case 'C': System.out.print("GRADE-C ");
}
A) GRADE-A
B) GRADE-B
C) GRADE-B GRADE-C
D) Compiler error
Answer [=] C
Explanation:"char" data type is allowed inside a Java SWITCH statement. The missing break statement causes CASE-C to be executed.
27) What is the output of the below Java program with SWICH and ENUM?
static enum ANIMAL {GOAT, TIGER, CAMEL}
public static void main(String args[])
{
ANIMAL ani = ANIMAL.CAMEL;
switch(ani)
{
case GOAT: System.out.println("GOAT");break;
case CAMEL: System.out.println("CAMEL");break;
case TIGER: System.out.println("TIGER");break;
}
}
A) CAMEL
B) GOAT
C) TIGER
D) Compiler error
Answer [=] A
Explanation:A SWITCH in java works well with enum constants. CASE Constants are defined without enum type.
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| Java Switch Case Interview MCQ Questions and Answers |
28) What is the output of the below Java program with SWITCH and Strings?
String phone = "APPLE";
switch(phone)
{
case "Apple": System.out.println("Apple");break;
case "APPLE": System.out.println("APPLE");break;
case "SAMSUNG": System.out.println("SAMSUNG");
}
A) Apple
B) APPLE
C) SAMSUNG
D) Compiler error
Answer [=] B
Explanation:Apple and APPLE are different strings.
