TASK:
Let's consider the following example:
if (!answer.isSuccessful()) {
result = "wrong"
} else {
result = answer.body().string()
}
return result
We need the following equivalent in Kotlin:
return ( !answer.isSuccessful() )
?
"wrong":
answer.body().string()
SOLUTION 1.a. You can use if-expression
in Kotlin:
return if (!answer.isSuccessful()) "wrong" else answer.body().string()
SOLUTION 1.b. It can be much better if you flip this if-expression
(let's do it without not
):
return if (answer.isSuccessful()) answer.body().string() else "wrong"
SOLUTION 2. Kotlin’s Elvis operator ?:
can do a job even better:
return answer.body()?.string() ?: "wrong"
SOLUTION 3. Or use an Extension function
for the corresponding Answer
class:
fun Answer.bodyOrNull(): Body? = if (isSuccessful()) body() else null
SOLUTION 4. Using the Extension function
you can reduce a code thanks to Elvis operator
:
return answer.bodyOrNull()?.string() ?: "wrong"
SOLUTION 5. Or just use when
operator:
when (!answer.isSuccessful()) {
parseInt(str) -> result = "wrong"
else -> result = answer.body().string()
}