accessing non-final property in constructor

class KafkaService {

  val producer: KafkaProducer<String, String>

  init {
    val props = Properties()
    props[ProducerConfig.BOOTSTRAP_SERVERS_CONFIG] = "127.0.0.1:9092"
    props[ProducerConfig.CLIENT_ID_CONFIG] = "DemoProducer"
    props[ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG] = StringSerializer::class.java.name
    props[ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG] = StringSerializer::class.java.name

    producer = KafkaProducer(props)
  }

  fun sendToKafka(topic: String, message: String) {
    val producerRecord: ProducerRecord<String?, String> = ProducerRecord(topic, null, message)
    producer.send(producerRecord)
  }
}

val <K, V>SortedMap<K, V>.first get() =...

getId()

override val id

JsonRpcResponse<R>

R

ClassLoader.getSystemResourceAsStream(filename)

null

Paths.get(".")

DefaultErrorMessages.java

inline fun <reified T: Any?> foo()

T

List<Something>

Something

internal

fun Boolean.throwIfTrue(exception: Exception) { if (this) throw exception }
fun Boolean.throwIfFalse(exception: Exception) { if (!this) throw exception }

for (i in 0 until someValue)

repeat(someValue)

Ideally, we'd like to support functions of arbitrary arity in Kotlin. In practice, a JVM method cannot have more that 255 parameters, so this is the limit for us as well.

inline class

inline class

Name?

String

String?

inline class Name(val s: String)
fun foo(n: Name?) { ... } // `Name?` here is mapped to String

@Deprecated(message = "java only", level = DeprecationLevel.HIDDEN)

@Suppress

ClassCastException

fun main(args: Array<String>) {
  fun <T> foo(block: () -> T): T = block()
  @Suppress("ConstantConditionIf")
  if (true) foo { "foo" }
}

for (entry in map) {
    if (myValue.startsWith(entry.key)) {
        myAction()
        return true
    }
}
return false