gson-flatten

Library to collapse inner objects when parsing json

To use library you should add it in your build.gradle:

    compile 'org.itishka.gson-flatten:gson-flatten:0.8.1'

Then register it in your gson builder:

final Gson gson = new GsonBuilder()
          .registerTypeAdapterFactory(new FlattenTypeAdapterFactory())
          .create();

Define your class and use @Flatten annotation to get data from embedded objects. For example class

class Weather {
  @Flatten("temperature::min")
  int min_temperture;
  @Flatten("temperature::max")
  int max_temperture;
}

will be filled with data from json

{
  "temperature": {
     "min": -273,
     "max": 1000
  }
}

Then just parse or serialize json as your usually do:

  String json = gson.toJson(weather);
  Weather weather2 = gson.fromJson(json, Weather.class);

Additional features

You can skip field name if it equlas in inner object and outer one. E.g.:

class Weather {
    @Flatten("temperature::")
    int min;
    @Flatten("temperature::")
    int max;
}

You can get array items as well (tnx @tominsam):

class SomeClass {
    @Flatten("some_array::0")
    int first_value;
}

If you are using Gson 2.7 with some FieldNamingStrategies with and gson-flatten 0.6 you do not need to do anything more!

With previous versions of gson and gson-flatten you should provide FieldNamingStrategy to FlattenTypeAdapterFactory:

final Gson gson = new GsonBuilder()
          .setFieldNamingPolicy(FieldNamingPolicy.UPPER_CAMEL_CASE)
          .registerTypeAdapterFactory(new FlattenTypeAdapterFactory(FieldNamingPolicy.UPPER_CAMEL_CASE))
          .create();

License

Based on https://github.com/noties/Flatten

Gson-flatten is released under LGPL 3.0 license

Tishka17/gson-flatten

gson-flatten

Library to collapse inner objects when parsing json

Additional features

License