Unable to parse JSON with GSON in Scala - scala

Question

I am using Gson to parse json to Scala, but error occured,the code is as follows, looks the Gson.fromJson(String, java.lang.reflect.Type type)
object GsonUtils {
val GSON = new GsonBuilder().create()
def java2Json(obj: Object) = GSON.toJson(obj)
def json2Java[T](json: String, tyze: Type) = GSON.fromJson(json, tyze)
}
case class Data(#BeanProperty val name: String, #BeanProperty val age: Int)
object GsonUtilsTest {
def main(args: Array[String]) {
val d = Data("1",1)
val json = GsonUtils.java2Json(d)
println(json)
//ERROR
val d2 = GsonUtils.json2Java(json, classOf[Data]).asInstanceOf[Data]
val dats = new java.util.ArrayList[Data]()
dats.add(Data("1",1))
val json2 = GsonUtils.java2Json(dats)
val tyze = new TypeToken[ java.util.List[Data]](){
}.getType()
//ERROR
GsonUtils.json2Java(json2,tyze)
}
}
When I run it, exception throws, the exception is:
Exception in thread "main" java.lang.ClassCastException: com.xyz.Data incompatible with scala.runtime.Nothing$
at java.lang.ClassCastException.<init>(ClassCastException.java:58)
at com.xyz.GsonUtils$.json2Java(GsonUtils.scala:18)
at com.xyz.GsonUtilsTest$.main(GsonUtils.scala:30)
at com.xyz.GsonUtilsTest.main(GsonUtils.scala)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:88)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:55)
at java.lang.reflect.Method.invoke(Method.java:613)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144)

Answer 1

Use fromJson(String json, Class classOfT) instead of fromJson(String json, Type typeOfT)
object GsonUtils {
val GSON = new GsonBuilder().create()
def java2Json(obj: Object) = GSON.toJson(obj)
//def json2Java[T](json: String, tyze: Type) = GSON.fromJson(json, tyze)
def json2Java[T](json: String, tyze: Class[T]) = GSON.fromJson(json, tyze)
}
case class Data(val name: String, val age: Int)
object GsonUtilsTest {
def main(args: Array[String]) {
val d = Data("1",1)
val json = GsonUtils.java2Json(d)
println(json)
val obj:Data = GsonUtils.json2Java(json, classOf[Data])
println(s"${obj}")
val d2:util.ArrayList[Data] = new util.ArrayList[Data]
d2.add(Data("1",1))
d2.add(Data("2",2))
val json2 = GsonUtils.java2Json(d2)
println(json2)
val dataclass = classOf[util.ArrayList[Data]]
val obj2:util.ArrayList[Data] = GsonUtils.json2Java(json2, dataclass)
println(s"${obj2}")
}
}