java - how to config gson to exclude 0 integer values

Question

I've a Java class with lot of integer fields and when I want to serialize them to json string due to some of them could have no value, hence after serializing all integers get zero as values ! I want to config gson not to serialize them if they do not have any values.

for example I have this class :

class Example {
   String title = "something";
   int id = 22;
   int userId;
} 

by default gson gives me this result :

{
   "title" : "something",
   "id" : 22,
   "userId" : 0
}

but i don't want the userId to be serialized when its value is 0. so the json should be:

{
   "title" : "something",
   "id" : 22
}

for objects by default gson doesn't serialize null objects is there a way to config gson not to serialize 0 numbers

Answer 1

We have to just use class Integer (Integer javadoc).

class Example {
   String title = "something";
   Integer id = 22;
   Integer userId;
}