Question

16) Describe what the break and continue statements do when executed in a loop.

17) What does a break statement do in a switch-case construct?

18) What method must be declared and implemented in any Java program? Provide the correct form of the first line of this method’s definition.

19) Describe the meanings of all the various parts of the definition from the prior problem.

Answer 1

16. function of break statement-

when we run any loop (while loop , for loop, do while loop) and we want to stop the execution of loop in any time(while loop is running) then this can be achieve by break statement.

this will be clear more with this example.

let a variable count =0; //initial value of count is 0;

for(i=1 ; i <=10 ; i++) // this loop run 10 times if we not introduce any break statement.

{ // in that case loop run for i=1 ,2,3,4,5,6,7,8,9,10

count =count+1;

print(count);

}

printf ("execution is here");

so output is 1 2 3 4 5 6 7 8 9 10

but if we use break inside loop then see,

initialize count =0;

for(i=1;i<=10;i++)

{

count=count+1; // in this case loop run for only i=1,2,3,4,5 after that loop is break

print(count);

if(count ==5)

{

break;

}

}

printf("execution is here");

in that case output is 1 2 3 4 5 and "execution is here" is printed;

it means when break statement is introduced in loop then it exit from loop and start execution outside of loop.

function of continue statement

when we run any loop (while loop , for loop, do while loop) and we want to stop the execution of any iteration of loop in any time(while loop is running) then this can be achieve by continue statement.

this will be clear more with this example.

let a variable count =0; //initial value of count is 0;

for(i=1 ; i <=10 ; i++) // this loop run 10 times if we not introduce any continue statement.

{ // in that case loop run for i=1 ,2,3,4,5,6,7,8,9,10

count =count+1;

print(count)

}

printf ("execution is here");

output will count=1 , 2 ,3 , 4, 5, 6, 7, 8, 9, 10 and  "execution is here" is printed.

but if we use continue statement inside loop then see,

initialize count =0;

for(i=1;i<=10;i++)

{

count=count+1; // in this case loop run for only i=1,2,3,4,6,7,8,9,10 but not for i=5;

if(count ==5) //when i=5 then it skip i=5 iteration of loop and start execution from i=6(i e stop for i=5);

{

continue;

}

print(count) ;

}

printf("execution is here");

in that case output is 1 2 3 4 6 7 8 9 10 and "execution is here" is printed;

it means when continue statement is introduced in loop then it stop execution of iterations of loop where it is called(here for i=5) continue is called.

17. function of break in switch case statement.

lets start with code .

int n=1;

switch(n)

case 1:

print(" hello 1");

break;

case 2:

print("hello 2");

break;

case 3:

print("hello 3")

break;

in above case n=1 so case 1 is executed and break is called in case 1.

so output will be hello 1 only and it exit from switch statement.

now if we don't introduce break statement then ,

int n=1;

switch(n)

case 1:

print(" hello 1");

case 2:

print("hello 2");

case 3:

print("hello 3")

then output will be hello 1 , hello 2 ,  hello 3 and then exit,

it means if we does not introduce break statement in switch case then it start executing also the below case(note - only below case is executed )

if n=2 in above example(without break statement example ) then output will be  hello 2 ,  hello 3 and then exit, here hello 1 is not printed because ,it is above the case 2.

hence , if break statement is not present in any case then it will execute that case and also all the decendent case till break is not found or cases are end;

18 .

the method that must be declared and implemented in any java program is main method ,

it is defined as public static void main(String args[]).

19 the meaning of various parts is

1 . public - main method should always be public because it can be called from outside of its class.

2. static - main method is static because static allow main method to be called without creating object of class of main method.

3. void -- because return type of main method is void(because it is called by JVM)

5 main - main is keyword for main method.

6. String args[] - it is array of strings which stores arguments passed by command line.