DSL-JSON doesn't support scala.collection.immutable.IntMap and scala.collection.mutable.LongMap

[plokhotnyuk]

No description provided.

[zapov]

I see there are some missing arguments so this could be easily supported even from outside the lib, which I'll look to add for next version.
But I'm not sure where to draw the line between nice to have and stuff which must be supported.
Library was built to be extendable and for this example that would look like:

 def primitiveMapWriter(manifest: Type, json: DslJson[_]) = {
   manifest match {
     case pt: ParameterizedType if pt.getRawType == classOf[IntMap[_]] =>
       val valueWriter = json.tryFindWriter(pt.getActualTypeArguments.head)
       val encoder = new ScalaMapEncoder[Int, Any](
         json,
         true,
         Some(NumberConverter.INT_WRITER.asInstanceOf[JsonWriter.WriteObject[Int]]),
         Some(valueWriter.asInstanceOf[JsonWriter.WriteObject[Any]]))
       json.registerWriter(manifest, encoder)
       encoder
     case _ => null
   }
 }

dslJson.registerWriterFactory(primitiveMapWriter)

[plokhotnyuk]

@zapov thanks for your help!

It isn't so easy to make it work properly for any types...
I have tried your implementation here, but it throws the following exception in runtime:

java.lang.ClassCastException: scala.Tuple2 cannot be cast to java.lang.Boolean
	at com.dslplatform.json.BoolConverter$3.write(BoolConverter.java:25)
	at com.dslplatform.json.runtime.IterableEncoder.write(IterableEncoder.scala:34)
	at com.dslplatform.json.runtime.IterableEncoder.write(IterableEncoder.scala:6)
	at com.github.plokhotnyuk.jsoniter_scala.benchmark.DslPlatformJson$.dslJsonEncode(DslPlatformJson.scala:96)
	at com.github.plokhotnyuk.jsoniter_scala.benchmark.IntMapOfBooleansBenchmark.writeDslJsonScala(IntMapOfBooleansBenchmark.scala:68)
	at com.github.plokhotnyuk.jsoniter_scala.benchmark.IntMapOfBooleansBenchmarkSpec.$anonfun$new$3(IntMapOfBooleansBenchmarkSpec.scala:26)