Demonstrating how to use Java Generic types with the Google's gson library

GsonGenericsSample.java

package io.github.farhadfaghihi;

import com.google.gson.Gson;
import com.google.gson.annotations.SerializedName;
import com.google.gson.reflect.TypeToken;

/**
 * This project shows a sample code for using java Generic Types de/serialization,
 * Google's gson library.
 * The project is about consuming the responses from a webservice, which all of its
 * responses have the structure of [code and data] as shown in the BaseResonse class
 * @see io.github.farhadfaghihi.BaseResponse
 * 
 * SampleResponse class is a realworld server response which extends the BaseResponse
 * @see io.github.farhadfaghihi.SampleResponse
 * 
 * The "mockResponse" string is going to be deserialized to an object of BaseResponse of type "SampleResponse"
 * @see io.github.farhadfaghihi.GsonGenericsSample#mockReponse
 * I think the rest is self-explanatory.
 * 
 * @author farhadfaghihi
 * @since 01-08-2017
 * @version 1.0
 * 
 */
public class GsonGenericsSample {

    private static String mockReponse = "{\n" +
            "\"code\" : 0 ,\n" +
            " \"data\" :\n" +
            " {\n" +
            "   \"sys_device_id\" : \"52\" ,\n" +
            "   \"sys_user_id\" : \"25\" ,\n" +
            "   \"is_activated\" : \"true\"\n" +
            " }\n" +
            "}" ;

    public static void main(String[] args) {

        BaseResponse<SampleResponse> response = new Gson().fromJson(mockReponse,new TypeToken<BaseResponse<SampleResponse>>(){}.getType()) ;

        System.out.println(response.getData().getDeviceId());

    }

    class BaseResponse<T> {

        private int code;
        private T data;

        public int getCode() {
            return code;
        }

        public void setCode(int code) {
            this.code = code;
        }

        public T getData() {
            return data;
        }

        public void setData(T data) {
            this.data = data;
        }
    }

    class SampleResponse {

        @SerializedName("sys_device_id")
        private String deviceId ;

        @SerializedName("sys_user_id")
        private String userId ;

        @SerializedName("is_activated")
        private boolean isActivated ;

        public String getDeviceId() {
            return deviceId;
        }

        public void setDeviceId(String deviceId) {
            this.deviceId = deviceId;
        }

        public String getUserId() {
            return userId;
        }

        public void setUserId(String userId) {
            this.userId = userId;
        }

        public boolean isActivated() {
            return isActivated;
        }

        public void setActivated(boolean activated) {
            isActivated = activated;
        }
    }
}