reading json file using jackson library in scala language - json

Question

I am newto the scala language to i am trying to read the json file in my scala file using jackson library
my son file is like this
{
"Rice":[
{
"name":"Basmati",
"price":40
},
{
"name":"jeera",
"price":30
},
{
"name":"Indrayani",
"price":40
}
],
"Pulses":[
{
"name":"peas",
"price":60
},
{
"name":"ground nut",
"price":60
},
{
"name":"dal",
"price":80
}
],
"Wheats":[
{
"name":"atta",
"price":40
},
{
"name":"bread",
"price":45
},
{
"name":"bun",
"price":50
}
]
}
I tried with the case classes to store and print the data
code sample like this
case class Inventory(var name:String,var price:String)
object InventoryDataManagement {
def main(args: Array[String]): Unit = {
val mapper = JsonMapper.builder()
.addModule(DefaultScalaModule)
.build()
val src = new File("src/main/json/inventary.json")
val myMap = mapper.readValue(src,classOf[Inventory])
println(myMap.name)
}
}
but I am getting error like below
Exception in thread "main" com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "Rice" (class Inventory), not marked as ignorable (2 known properties: "price",
"name"])
please help to understand this
thanks in advance!!!

Answer 1

Unrecognized field "Rice" (class Inventory)
This error should make you notice that Jackson is looking for a field Rice on the Inventory class, which doesn't make sense.
Why so?
Because you are telling Jackson to read your JSON file as a single Inventory instance.
This is not what your JSON file contains, it contains something that can be represented as a Map[String, Seq[Inventory]].
You should try something like this instead:
mapper.readValue(src,classOf[Map[String, Seq[Inventory]]])