Kotlin-JsonParser

Kotlin-JsonParser is a Kotlin library for JSON parsing. It can parse JSON string to Kotlin Object or reverse in a simple way.

#Feature

One line parsing

• you can parse json to object or object to json in one line code

Annotation Configuration

• Support annotation for enabling/disabling features (e.g. serialization), see also here

flexible custom class serialize and deserialize

• Support TypeAdapter for custom deserialize and serialize process, see also here

Retrofit Ready

• ConverterFactory of Retrofit already implemented in JsonConverterFactory, see also here

Getting Started

Installation

To use Kotlin-JsonParser in gradle implemented project,

dependencies {
	...
	implementation 'com.tomatobean:jsonparser:1.0.10'
	...
}

Usage

For parsing JSON String to Kotlin Object, it can be done by one line comment.

	val kotlinObject = jsonString.parseJson(KotlinObject::class)

P.S. For Json parsing, all immutable params must be in the Primary Constructor of Kotlin Object

    data class KotlinObject(
        val paramOne: String,
        val paramTwo, Int,
        ....
    )

And it is also easy for parsing kotlin Object to JSON String.

	val jsonString = kotlinObject.toJson()

Annotation

Using Annotation for config Json parsing process

data class ClassA(@JsonFormat(JsonName = "jsonNameString")
                   val stringA: String,
                   @JsonFormat(JsonName = "nonDeserializableString", Deserializable = false)
                   val stringB: String = "stringB",
                   @JsonFormat(JsonName = "nonDeserializableString", Serializable = false)
                   val stringC: String = "stringC")
                                           

JsonFormat class have the following params can config

JsonName

• the json paring name tag for serialize and deserialize, variable name will be use when it is not set

Serializable

• the variable will not parse to json when it set to false (default is true)

Deserializable

• the variable will not parse from json when it set to false (default is true)

TypAdapter

For custom deserialize process, DeserializeAdapter and SerializeAdapter interface can implement for custom process

DeserializeAdapter usage demonstration can be found in /app module

    val abstractObjectDeserializer: DeserializeAdapter<AbstractObject> = object: DeserializeAdapter<AbstractObject> {
    
            override fun read(json: String, config: JsonParserConfig): AbstractObject? {
                val jsonObj = JSONObject(json)
                if (jsonObj.has("tag") && jsonObj.getString("tag").isNotEmpty()) {
                    val classType = jsonObj.getString("tag")
                    return switchJson(classType, json)
                }
                return null
            }
    
            private fun switchJson(classType: String, jsonString: String): AbstractObject? =
                    when (classType) {
                        "classA" -> {
                            jsonString.parseJson(ChildClassA::class)
                        }
                        "classB" -> {
                            jsonString.parseJson(ChildClassB::class)
                        }
                        "classC" -> {
                            jsonString.parseJson(ChildClassC::class)
                        }
                        else -> null
                    }
        }

and create JsonFormatter instance by the following way

    val jsonFormatter = JsonFormatter(deserializeAdapterMap = hashMapOf(
                AbstractObject::class to abstractObjectDeserializer
        ))

For more usage example, you can reference to /app module

TypeToken

KotlinJsonParser also support List, Map class for parsering

    val kotlinObjectList = json.parserJson(object: TypeToke<List<KotlinObject>>(){})
    val json = kotlinObjectList.toJson()

For Generic Abstract class for parsering

    abstract class GenericDataSource<DATA>: TypeToken<DATA> {
        fun parserJson(json: String) {
	    json.parserJson(this)
	}
    }

JsonConverterFactory

KotlinJsonParser already support Retrofit By adding JsonConverterFactory into retrofit service, it can convert the network response to corresponding kotlin object

   Retrofit.Builder().addConverterFactory(JsonConverterFactory())
   ....

Authors

• Hin Lai - Initial work
• Wingy Ng - Initial work

License

This project is licensed under the MIT License - see the LICENSE.md file for details