utkan

Table of Contents

• 0.1. References
  • 0.2. Other cheatsheets
  • 0.3. Manage multiple gcloud config configurations
    • 0.3.1. Switch gcloud context with gcloud config
  • 0.4. Auth
• 0.5. info

utkan

import java.math.BigInteger

interface Fibonacci {
  fun fib(n: Int): Int
}

object LawfulGood : Fibonacci {
  override fun fib(n: Int): Int {
    check(n >= 0) { "fib is undefined for negative values: $n" }
    return when (n) {

utkan

inline fun <VM : ViewModel> viewModelFactory(
    crossinline f: () -> VM) =
        object : ViewModelProvider.Factory {
            override fun <T : ViewModel> create(aClass: Class<T>) = 
                f() as T
        }

private val viewModel by lazy {
    val factory = viewModelFactory { component.myViewModel() }
    ViewModelProviders.of(this, factory)

utkan

class NotificationParams(val map: Map<String, String>) {
    val title: String by map
    val content: String by map
}

override fun onMessageReceived(message: RemoteMessage?) {
    super.onMessageReceived(message)
    val data = (message?.data ?: emptyMap()).withDefault { "" }

    val params = NotificationParams(data)

utkan

import android.content.Context;
import android.os.Debug;
import java.io.File;

public class OomExceptionHandler implements Thread.UncaughtExceptionHandler {

  private static final String FILENAME = "out-of-memory.hprof";

  public static void install(Context context) {
    Thread.UncaughtExceptionHandler defaultHandler = Thread.getDefaultUncaughtExceptionHandler();

utkan

import java.util.concurrent.Callable;

public enum Lol implements Callable<CharSequence> {

  ಠ_ಠ {
    @Override public String call() {
      return "Foo";
    }
  };

utkan

sealed class BundleDelegate<T>(protected val key: kotlin.String) : ReadWriteProperty<Bundle, T> {

    class Int(key: kotlin.String) : BundleDelegate<kotlin.Int>(key) {
        override fun getValue(thisRef: Bundle, property: KProperty<*>) = thisRef.getInt(key)

        override fun setValue(thisRef: Bundle, property: KProperty<*>, value: kotlin.Int) {
            thisRef.putInt(key, value)
        }
    }

utkan

interface Dependency<T> {
    var mocked: T?
    fun get(): T
    fun lazyGet(): Lazy<T> = lazy { get() }
}

class Provider<T>(val init: () -> T) : Dependency<T> {
    var original: T? = null
    override var mocked: T? = null
    override fun get(): T = mocked ?: original ?: init().apply { original = this }

utkan

abstract class Provider<T> {
    var orginal: T? = null
    var mocked: T? = null

    abstract fun create(): T

    fun get(): T = mocked ?: orginal ?: create().apply {
        orginal = this
    }

utkan

enum class Rank {
    TWO, THREE, FOUR, FIVE,
    SIX, SEVEN, EIGHT, NINE,
    TEN, JACK, QUEEN, KING, ACE;

    fun of(suit: Suit) = Card(this, suit)
}

enum class Suit {
    HEARTS,