Package com.google.gson.annotations

Annotation Type Since

@Documented
@Retention(RUNTIME)
@Target({FIELD,TYPE})
public @interface Since

An annotation that indicates the version number since a member or a type has been present. This annotation is useful to manage versioning of your Json classes for a web-service.

This annotation has no effect unless you build Gson with a GsonBuilder and invoke GsonBuilder.setVersion(double) method.

Here is an example of how this annotation is meant to be used:

 public class User {
   private String firstName;
   private String lastName;
   @Since(1.0) private String emailAddress;
   @Since(1.0) private String password;
   @Since(1.1) private Address address;
 }
 

If you created Gson with new Gson(), the toJson() and fromJson() methods will use all the fields for serialization and deserialization. However, if you created Gson with Gson gson = new GsonBuilder().setVersion(1.0).create() then the toJson() and fromJson() methods of Gson will exclude the address field since it's version number is set to 1.1.

Required Element Summary

Required Elements

Modifier and Type	Required Element	Description
double	value	the value indicating a version number since this member or type has been present.

Element Detail

value

double value

the value indicating a version number since this member or type has been present.