linearLayoutManager = new LinearLayoutManager(context) {
 @Override
 public boolean canScrollVertically() {
  return false;
 }
};

val description = descriptionTextView.text.toString().takeUnless { it.isBlank() } ?: "A DefaultString"

val (one, two, three) = listOf(0,  0, 0)

val (one, two, three) = IntArray(3) { 0 }

val statusMap = mutableMapOf(
            noreply to 0, contacted to 0, finished to 0,
            negotiating to 0, sold to 0, notContacted to 0
        )

        searchResults.forEach {
            if (statusMap.containsKey(it.state)) {
                statusMap[it.state] = statusMap.getValue(it.state) + 1
            }
        }

val a = listOf(Pair("a", 1), Pair("a", 2), Pair("b", 1))

[(a, 3), (b, 1)]

a.groupBy ({ it.first}, {it.second} ).map{(key, value) -> key to value.sum()}

a.groupByKey{(x,y) -> x+y}

x

y

object.wait()

object.notify()

Object

Any?

wait()

notify()

Any

it

kotlin
val test: Pair<String, (String) -> Boolean> = "length is 6" to { input -> input.length == 6 }

it

?.let

.let

@Entity
data class Form(@Id @GeneratedValue override var id: Long? = null,
                override var date: Date? = null,
                override var name:String? = null) : Post

class Foo internal constructor() {
    var bar: Int = 0
    private set

    var fuz: String = ""
    private set

    constructor(a: Int, b: String) : this(){
        this.bar = a
        this.fuz = b
    }
}

var foo = Foo(9,"hello world")

KCallable

class ExampleClass(private val targetClass: KClass<*>, private val solution: KCallable<*>) {

    private val studentMethod by lazy {
        var methodFinding: KCallable<*>? = null
        for (m: KCallable<*> in targetClass.declaredMembers) {
            if (m.name == solution.name && (methodFinding == null || validateParameterTypes(m))) {
                methodFinding = m
            }
        }
        methodFinding
    }

    private fun validateParameterTypes(m: KCallable<*>): Boolean { ... }
}

@Configuration
class MetricsConfig {
   @Bean
   fun commonTags(): MeterRegistryCustomizer<MeterRegistry> = { registry ->    
      registry.config().commonTags("kenneth", "kenneth2")
   }
}

Inferred type is a function type, but a non-function type MeterRegistryCustomizer<MeterRegistry> was expected. Use either '= ...' or '{ ... }', but not both

override fun equals(other: Any?): Boolean {
        if (this === other) return true
        if (javaClass != other?.javaClass) return false

        other as Model

        if (name != other.name) return false
        if (lastName != other.lastName) return false
        if (password != other.password) return false

        return true
    }

override fun equals(other: Any?): Boolean {
        if (this === other) return true
        if (javaClass != other?.javaClass) return false

        other as Model

        return name == other.name
                && lastName == other.lastName
                && password == other.password

    }

override fun equals(other: Any?): Boolean {
        return this === other
                || javaClass == other.javaClass
                && name == other.name
                && lastName == other.lastName
                && password == other.password
    }

interface AclClassRepository : PagingAndSortingRepository<AclClass, Long>

@Component
    class SecurityConfiguration(private val classRepo: AclClassRepository) : WebSecurityConfigurerAdapter() {

        @PostConstruct
        private fun init() {
            val context = SecurityContextHolder.getContext()
            context.authentication = UsernamePasswordAuthenticationToken("system", "system",
                    createAuthorityList("ROLE_ADMIN"))


            val all = classRepo.findAll()
            val reflections = Reflections(this.javaClass.`package`.name)

            val entities = all - reflections.getTypesAnnotatedWith(Entity::class.java)

           // Error:(64, 42) Kotlin: Type parameter bound for S in fun <S : AclClass!> save(p0: S): S
 is not satisfied: inferred type Any! is not a subtype of AclClass!

            entities.forEach { classRepo.save(it) }

//Error:(65, 23) Kotlin: Type parameter bound for S in fun <S : AclClass!> saveAll(p0: (Mutable)Iterable<S!>): (Mutable)Iterable<S!>
 is not satisfied: inferred type Any! is not a subtype of AclClass!

            classRepo.saveAll(entities)


            SecurityContextHolder.clearContext()

        }
}

ctrl+Q

fun turnOn() { state = true }