How to use com.google.gson

 JsonObject data = new Gson().fromJson(request.getReader(), JsonObject.class);
String foo = data.get("foo").getAsString();
String bar = data.get("bar").getAsString();
String baz = data.get("baz").getAsString();
// ...

  private static <T> void populate(GsonBuilder builder, String json, Class<T> type, final T into) {
    builder.registerTypeAdapter(type, (InstanceCreator<T>) t -> into)
        .create()
        .fromJson(json, type);
  }
}

/**
 * Construct a new {@code GsonHttpMessageConverter} with default configuration.
 */
public GsonHttpMessageConverter() {
  this.gson = new Gson();
}

 Editor prefsEditor = mPrefs.edit();
Gson gson = new Gson();
String json = gson.toJson(myObject); // myObject - instance of MyObject
prefsEditor.putString("MyObject", json);
prefsEditor.commit();

 Gson gson = new GsonBuilder().setPrettyPrinting().create();
JsonParser jp = new JsonParser();
JsonElement je = jp.parse(uglyJSONString);
String prettyJsonString = gson.toJson(je);

 public String parse(String jsonLine) {
  JsonElement jelement = new JsonParser().parse(jsonLine);
  JsonObject  jobject = jelement.getAsJsonObject();
  jobject = jobject.getAsJsonObject("data");
  JsonArray jarray = jobject.getAsJsonArray("translations");
  jobject = jarray.get(0).getAsJsonObject();
  String result = jobject.get("translatedText").toString();
  return result;
}

public static JadxSettings fromString(String jsonSettings) {
  return GSON.fromJson(jsonSettings, JadxSettings.class);
}

private static String gsonPrettyPrint( final String json )
{
  JsonElement element = JSON_PARSER.parse( json );
  return GSON.toJson( element );
}

public static String makeString(JadxSettings settings) {
  return GSON.toJson(settings);
}

/**
 * Obtain a {@link GsonBuilder} which Base64-encodes {@code byte[]}
 * properties when reading and writing JSON.
 * <p>A custom {@link com.google.gson.TypeAdapter} will be registered via
 * {@link GsonBuilder#registerTypeHierarchyAdapter(Class, Object)} which
 * serializes a {@code byte[]} property to and from a Base64-encoded String
 * instead of a JSON array.
 */
public static GsonBuilder gsonBuilderWithBase64EncodedByteArrays() {
  GsonBuilder builder = new GsonBuilder();
  builder.registerTypeHierarchyAdapter(byte[].class, new Base64TypeAdapter());
  return builder;
}

  @Override
  public byte[] deserialize(JsonElement json, Type type, JsonDeserializationContext cxt) {
    return Base64Utils.decodeFromString(json.getAsString());
  }
}

 @Override public T convert(ResponseBody value) throws IOException {
  JsonReader jsonReader = gson.newJsonReader(value.charStream());
  try {
   T result = adapter.read(jsonReader);
   if (jsonReader.peek() != JsonToken.END_DOCUMENT) {
    throw new JsonIOException("JSON document was not fully consumed.");
   }
   return result;
  } finally {
   value.close();
  }
 }
}

Editor prefsEditor = mPrefs.edit();
  Gson gson = new Gson();
  String json = gson.toJson(MyObject);
  prefsEditor.putString("MyObject", json);
  prefsEditor.commit();

 @Override
 public T apply(String input) {
  return gson.fromJson(input, responseType);
 }
};

 public static String batchTransformToJSON(Set<GrayReleaseRuleItemDTO> ruleItems) {
  return gson.toJson(ruleItems);
 }
}

 Type listType = new TypeToken<ArrayList<YourClass>>(){}.getType();

List<YourClass> yourClassList = new Gson().fromJson(jsonArray, listType);

/**
 * Describe a Java interface in Json schema.
 *
 * @return Service description
 */
public static String schema(final Class<?> clazz) {
  ServiceDefinition sd = build(clazz);
  Gson gson = new Gson();
  return gson.toJson(sd);
}

 @Override
 public T apply(String input) {
  return gson.fromJson(input, responseType);
 }
};

/**
 * Create an instance using a default {@link Gson} instance for conversion. Encoding to JSON and
 * decoding from JSON (when no charset is specified by a header) will use UTF-8.
 */
public static GsonConverterFactory create() {
 return create(new Gson());
}

/**
 * Describe a Java interface in Json schema.
 *
 * @return Service description
 */
public static String schema(final Class<?> clazz) {
  ServiceDefinition sd = build(clazz);
  Gson gson = new Gson();
  return gson.toJson(sd);
}