A modern programming language that makes developers happier.

kotlinlang

ok, Guest has two constructors generated by Kotlin:

```
  public &lt;init&gt;(Ljava/lang/String;Ljava/lang/String;Lcom/fasterxml/jackson/module/kotlin/test/TestCasesFromSlack$RSVP;)V
  @Lcom/fasterxml/jackson/annotation/JsonCreator;()
    @Lcom/fasterxml/jackson/annotation/JsonProperty;(value="id") // parameter 0
    @Lcom/fasterxml/jackson/annotation/JsonProperty;(value="name") // parameter 1
    @Lcom/fasterxml/jackson/annotation/JsonProperty;(value="rsvp") // parameter 2
    @Lorg/jetbrains/annotations/NotNull;() // invisible, parameter 0
    @Lorg/jetbrains/annotations/NotNull;() // invisible, parameter 1
    @Lorg/jetbrains/annotations/NotNull;() // invisible, parameter 2

```

and

```
  // access flags 0x1001
  public synthetic &lt;init&gt;(Ljava/lang/String;Ljava/lang/String;Lcom/fasterxml/jackson/module/kotlin/test/TestCasesFromSlack$RSVP;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
  @Lcom/fasterxml/jackson/annotation/JsonCreator;()
 
```

second is synthetic but they copy the annotation JsonCreator to it.  This causes Jackson to see it, and maybe is picking the wrong constructor.  Although two JsonCreator should cause an error.