sample lambda expression in kotlin & decompile into java

KtTestLambda.kt

package th.`in`.lordgift.test

class KtTestLambda {

    companion object {
        @JvmStatic
        fun main(args: Array<String>) {
            println("Hello, world!")
            TestLambda.call()
        }


        fun call() {
            //---------------------- Anonymous Function
            val sum = { x: Int, y: Int -> x + y }
            println(sum(2, 3))

            //---------------------- Passing Declared Anonymous Function
            println(higherOrder(sum))

            //---------------------- Passing Anonymous Function
            println(higherOrder { i1, i2 -> i1+i2+100 })


            //---------------------- Multi Function
            higherOrder({
                println("ok callback")
            }, { e ->
                error(e)
            })


            //---------------------- built-in receiver
            val arr = ArrayList<String>()
            arr.add("INDEX 1")
            arr.forEach { e -> e + "XXX" }
        }

        /**
         * single lambda receiver
         */
        fun higherOrder(f: (Int, Int) -> Int): String {
            return "This is result of f(1, 2) : " + f(1,2)
        }

        /**
         * multiple lambda receivers
         */
        fun higherOrder(ok: () -> Unit, fail: (Throwable) -> Unit) {
            try {
                ok()
                throw Exception("fake error")
            } catch (e: Throwable) {
                fail(e)
            }
        }
    }

}

KtTestLambda.kt.java

//Decompile to Java from compiled KtTestLambda.kt
package th.in.lordgift.test;

import java.util.ArrayList;
import java.util.Iterator;
import kotlin.Metadata;
import kotlin.jvm.JvmStatic;
import kotlin.jvm.functions.Function0;
import kotlin.jvm.functions.Function1;
import kotlin.jvm.functions.Function2;
import kotlin.jvm.internal.DefaultConstructorMarker;
import kotlin.jvm.internal.Intrinsics;
import org.jetbrains.annotations.NotNull;

@Metadata(
   mv = {1, 1, 11},
   bv = {1, 0, 2},
   k = 1,
   d1 = {"\u0000\f\n\u0002\u0018\u0002\n\u0002\u0010\u0000\n\u0002\b\u0003\u0018\u0000 \u00032\u00020\u0001:\u0001\u0003B\u0005¢\u0006\u0002\u0010\u0002¨\u0006\u0004"},
   d2 = {"Lth/in/lordgift/test/KtTestLambda;", "", "()V", "Companion", "KtDecompile"}
)
public final class KtTestLambda {
   public static final KtTestLambda.Companion Companion = new KtTestLambda.Companion((DefaultConstructorMarker)null);

   @JvmStatic
   public static final void main(@NotNull String[] args) {
      Companion.main(args);
   }

   @Metadata(
      mv = {1, 1, 11},
      bv = {1, 0, 2},
      k = 1,
      d1 = {"\u0000<\n\u0002\u0018\u0002\n\u0002\u0010\u0000\n\u0002\b\u0002\n\u0002\u0010\u0002\n\u0002\b\u0002\n\u0002\u0018\u0002\n\u0000\n\u0002\u0018\u0002\n\u0002\u0010\u0003\n\u0002\u0010\u000e\n\u0000\n\u0002\u0018\u0002\n\u0002\u0010\b\n\u0002\b\u0002\n\u0002\u0010\u0011\n\u0002\b\u0002\b\u0086\u0003\u0018\u00002\u00020\u0001B\u0007\b\u0002¢\u0006\u0002\u0010\u0002J\u0006\u0010\u0003\u001a\u00020\u0004J(\u0010\u0005\u001a\u00020\u00042\f\u0010\u0006\u001a\b\u0012\u0004\u0012\u00020\u00040\u00072\u0012\u0010\b\u001a\u000e\u0012\u0004\u0012\u00020\n\u0012\u0004\u0012\u00020\u00040\tJ \u0010\u0005\u001a\u00020\u000b2\u0018\u0010\f\u001a\u0014\u0012\u0004\u0012\u00020\u000e\u0012\u0004\u0012\u00020\u000e\u0012\u0004\u0012\u00020\u000e0\rJ\u001b\u0010\u000f\u001a\u00020\u00042\f\u0010\u0010\u001a\b\u0012\u0004\u0012\u00020\u000b0\u0011H\u0007¢\u0006\u0002\u0010\u0012¨\u0006\u0013"},
      d2 = {"Lth/in/lordgift/test/KtTestLambda$Companion;", "", "()V", "call", "", "higherOrder", "ok", "Lkotlin/Function0;", "fail", "Lkotlin/Function1;", "", "", "f", "Lkotlin/Function2;", "", "main", "args", "", "([Ljava/lang/String;)V", "KtDecompile"}
   )
   public static final class Companion {
      @JvmStatic
      public final void main(@NotNull String[] args) {
         Intrinsics.checkParameterIsNotNull(args, "args");
         String var2 = "Hello, world!";
         System.out.println(var2);
         KtTestLambda.Companion.call();
      }

      public final void call() {
         Function2 sum = (Function2)null.INSTANCE;
         int var2 = ((Number)sum.invoke(2, 3)).intValue();
         System.out.println(var2);
         String var9 = ((KtTestLambda.Companion)this).higherOrder(sum);
         System.out.println(var9);
         var9 = ((KtTestLambda.Companion)this).higherOrder((Function2)null.INSTANCE);
         System.out.println(var9);
         ((KtTestLambda.Companion)this).higherOrder((Function0)null.INSTANCE, (Function1)null.INSTANCE);
         ArrayList arr = new ArrayList();
         arr.add("INDEX 1");
         Iterable $receiver$iv = (Iterable)arr;
         Iterator var4 = $receiver$iv.iterator();

         while(var4.hasNext()) {
            Object element$iv = var4.next();
            String e = (String)element$iv;
            (new StringBuilder()).append(e).append("XXX").toString();
         }

      }

      @NotNull
      public final String higherOrder(@NotNull Function2 f) {
         Intrinsics.checkParameterIsNotNull(f, "f");
         return "This is result of f(1, 2) : " + ((Number)f.invoke(1, 2)).intValue();
      }

      public final void higherOrder(@NotNull Function0 ok, @NotNull Function1 fail) {
         Intrinsics.checkParameterIsNotNull(ok, "ok");
         Intrinsics.checkParameterIsNotNull(fail, "fail");

         try {
            ok.invoke();
            throw (Throwable)(new Exception("fake error"));
         } catch (Throwable var4) {
            fail.invoke(var4);
         }
      }

      private Companion() {
      }

      // $FF: synthetic method
      public Companion(DefaultConstructorMarker $constructor_marker) {
         this();
      }
   }
}