How to de-serialize POJO contains HashTable? - gson

Question

I have pojo like this:
public class Test implements java.io.Serializable {
private static final long serialVersionUID = 1L;
private String hash;
private java.util.Hashtable<Integer, Long> myTempTable;
public java.util.Hashtable<Integer, Long> getMyTempTable() {
return this.myTempTable;
}
public void setMyTempTable(java.util.Hashtable<Integer, Long> myTempTable) { this.myTempTable = myTempTable; }
//And some few variables
}
In response I get this POJO in JSON format but while converting this JSON to "Test" java object like this.
gson.fromJson(tempString, Test.class);
It is giving error as
java.lang.IllegalArgumentException: Can not set java.util.Hashtable field <package_name>.Temp.myTempTable to java.util.LinkedHashMap
Why GSON is converting HashTable to LinkedHashMap?
And does this error means?
UPDATE: JSON File as
{
"hash": "abc",
"myTempTable": {
"1": 30065833999,
"2": 34364325903,
"3": 536872959
}
}

Answer 1

For converting an Object to JSON String.
public static <T> String convertObjectToStringJson(T someObject, Type type) {
Gson mGson = new Gson();
String strJson = mGson.toJson(someObject, type);
return strJson;
}
For converting a JSON String to an Object.
public static <T> T getObjectFromJson(String json, Type type) {
Gson mGson = new Gson();
if (json != null) {
if (json.isEmpty()) {
return null;
}
}
return mGson.fromJson(json, type);
}
where
Type is type of your Object.
ex:
for object:
new TypeToken<YOUR_POJO>(){}.getType();
for list:
new TypeToken<List<YOUR_POJO>>(){}.getType();