Kotlin Return and Jump

There are three jump expressions in Kotlin. These jump expressions are used for control the flow of program execution. These jump structures are:

• break
• continue
• return

Break Expression

A break expression is used for terminate the nearest enclosing loop. It is almost used with if-else condition.

for(..){  
       //body of for  
       if(checkCondition){  
           break;  
       }  
}  
for(..){  
       //body of for  
       if(checkCondition){  
           break;  
       }  
}  

In the above example, for loop terminates its loop when if condition execute break expression.

fun main(args: Array< String>) {  
    for (i in 1..5) {  
        if (i == 3) {  
            break  
        }  
        println(i)  
    }  
}  
fun main(args: Array< String>) {  
    for (i in 1..5) {  
        if (i == 3) {  
            break  
        }  
        println(i)  
    }  
}  			  

1
2

In the above example, when the value of i became equal to 3 and satisfy the if condition(i==3) than the break expression execute and terminate for loop.

Kotlin Labeled break Expression

Labeled is the form of identifier followed by the @ sign, for example abc@, test@. To make an expression as label, we just put a label in front of expression.
Kotlin labeled break expression is used to terminate the specific loop. This is done by using break expression with @ sign followed by label name (break@loop).

fun main(args: Array< String>) {  
    loop@ for (i in 1..3) {  
        for (j in 1..3) {  
            println("i = $i and j = $j")  
            if (i == 2)  
                break@loop  
        }  
    }  
}  
fun main(args: Array< String>) {  
    loop@ for (i in 1..3) {  
        for (j in 1..3) {  
            println("i = $i and j = $j")  
            if (i == 2)  
                break@loop  
        }  
    }  
} 

i = 1 and j = 1
i = 1 and j = 2
i = 1 and j = 3
i = 2 and j = 1

In the above example, when the value of i became 2 and satisfy the if condition which execute break expression followed by labeled name. The break expression followed by labeled name terminates the body of label identifier.