Moshi adapter for org.json objects

SimpleJsonAdapter.kt

package com.n7mobile.loterity.network.moshi

import com.squareup.moshi.JsonAdapter
import com.squareup.moshi.JsonReader
import com.squareup.moshi.JsonReader.Token.END_ARRAY
import com.squareup.moshi.JsonReader.Token.END_OBJECT
import com.squareup.moshi.JsonWriter
import org.json.JSONArray
import org.json.JSONObject

class SimpleJsonAdapter : JsonAdapter<JSONObject>() {
    override fun fromJson(reader: JsonReader): JSONObject? =
            reader.readObject()

    override fun toJson(writer: JsonWriter, value: JSONObject?) {
        TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
    }
}

private fun JsonReader.readValue(): Any? =
        peek().let { token ->
            when (token) {
                JsonReader.Token.BEGIN_ARRAY -> readArray()
                JsonReader.Token.BEGIN_OBJECT -> readObject()
                JsonReader.Token.STRING -> "\"${nextString()}\""
                JsonReader.Token.NUMBER -> nextNumber()
                JsonReader.Token.BOOLEAN -> nextBoolean()
                JsonReader.Token.NULL -> nextNull() ?: null // elvis+null necessary for type inference
                else -> throw com.squareup.moshi.JsonEncodingException("Unexpected token: $token")
            }
        }

private fun JsonReader.nextNumber(): Number {
    try {
        return nextInt()
    } catch (ignored: Throwable) {
    }

    try {
        return nextLong()
    } catch (ignored: Throwable) {
    }

    return nextDouble()
}

private fun JsonReader.readObject(): JSONObject {
    val jsonObject = JSONObject()

    beginObject()
    while (peek() != END_OBJECT) {
        jsonObject.put(nextName(), readValue())
    }
    endObject()

    return jsonObject
}

private fun JsonReader.readArray(): JSONArray {
    val jsonArray = JSONArray()

    beginArray()
    while (peek() != END_ARRAY) {
        jsonArray.put(readJsonValue())
    }
    endArray()

    return jsonArray
}

The JsonReader.nextNumber() can be shortened to the following. Just a suggestion, thanks for your contribution!

private fun JsonReader.nextNumber(): Number {
    return try {
        nextInt()
    } catch (ignored: Throwable) {
        nextLong()
    } catch (ignored: Throwable) {
        nextDouble()
    }
}

How to use this one?

The JsonReader.nextNumber() can be shortened to the following. Just a suggestion, thanks for your contribution!

private fun JsonReader.nextNumber(): Number {
    return try {
        nextInt()
    } catch (ignored: Throwable) {
        nextLong()
    } catch (ignored: Throwable) {
        nextDouble()
    }
}

This won't work though, because if nextLong() throws an exception, it won't be caught in the second catch block, so nextDouble() will never be called.

How to use this one?

I've written this one a while ago so it's highly probable that it won't work with the current Moshi release. Nevertheless, you can find the docs about how to register a custom type adapter in the README on the Moshi repo: https://github.com/square/moshi