Issue with Gson deserialization when not handling specific fields
public class Mode {
@Expose(deserialize = false)
public final List<String> list;
public Mode(List<String> list) {
this.list = list;
}
public List<String> getList() {
return list;
}
}
List objects only serialize and do not deserialize in this scenario
public class Entity {
public Mode setting = new Mode(Arrays.asList("1", "2"));
}
Solution involves adding a deserialization exclusion strategy:
Gson gson = new GsonBuilder().setPrettyPrinting().addDeserializationExclusionStrategy(new ExclusionStrategy() {
@Override
public boolean shouldSkipField(FieldAttributes f) {
Expose annotation = f.getAnnotation(Expose.class);
if (annotation == null) {
return false;
}
return !annotation.deserialize();
}
@Override
public boolean shouldSkipClass(Class<?> clazz) {
return false;
}
}).create();
var s = """
{
"setting": {
"list": [
"1",
"2",
"3"
]
}
}
""";
System.out.println(gson.fromJson(s, Entity.class).setting.getList());
Error occurs where the list field of the Mode class returns as null during deserialization of the Entity class