Java Control Statements 01

Which of these is not a Control statement in Java?

• ? and :

• if-else

• switch

• do-while

• return

Answer explanation

The '? and :' operators are known as the ternary conditional operator in Java, not control statements. Control statements include 'if-else', 'switch', and 'do-while', which control the flow of execution.

Which of the following statements test only for equality?

• if

• switch

• for

• while

Answer explanation

We can use all relational operators for conditions with if, for and while but the switch statement compares only for equality condition of variable's value with case values.

Fill in the blanks such that the following code must display "Hello" on the screen.

int x = 19;

if(x ___ 19) System.out.print("Hello"); else System.out.print("Bye");

Answer explanation

To display 'Hello', the condition must be true. Using '==' checks if x is equal to 19. Therefore, the correct choice is '==' which allows the code to print 'Hello' when x is 19.

Choose the most appropriate of the options that apply to the following code segment:

char section = 'C';

switch(section) {

default: System.out.println("Mix batch");

case 'A': System.out.println("Toppers"); break;

}

• Compiler Error: the default case not allowed to be written before other cases.

• Compiler error : Must use break after every case

• Compiler error: Cannot use char variables as switch parameter

• Output:

  Mix batch

  Toppers

• Output:

  Mix batch

Answer explanation

The switch statement evaluates 'section' as 'C', which does not match any case. It falls to the default case, printing 'Mix batch'. Due to missing break statement after the default case, the case 'A' will also be executed, so 'Toppers' is also printed. Thus, the output is:

Mix batch

Toppers

Spot the location(s) reported for syntax error in the following code:

class Demo{

public static void main(String args[]) { //Line-1

int expense = 1_000; //Line-2

while(expense++ < 1100) ; //Line-3

{ boolean canSpendMore = true; return; } //Line-4

System.out.println(expense); //Line-5

} }

Tick all that apply.

• Line-1

• Line-2

• Line-3

• Line-4

• Line-5

Answer explanation

Line-5 has a syntax error because it is outside of any method or block after the return statement in Line-4. The return statement exits the method, making any code after it unreachable.