GsonHelper.java

/**
 * Gson type adapter to serialize and deserialize byte arrays in base64, 
 * removed class from android package and added java.util.Base64 encoder and decoder.
 * Forked from: (orip)[https://gist.github.com/orip/3635246]
 */
import java.lang.reflect.Type;



import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonParseException;
import com.google.gson.JsonPrimitive;
import com.google.gson.JsonSerializationContext;
import com.google.gson.JsonSerializer;
import java.util.Base64;

public class GsonHelper {
    public static final Gson customGson = new GsonBuilder().registerTypeHierarchyAdapter(byte[].class,
            new ByteArrayToBase64TypeAdapter()).create();

    // Using java.util.Base64 libraries. This can be replaced with any base64 library.
    private static class ByteArrayToBase64TypeAdapter implements JsonSerializer<byte[]>, JsonDeserializer<byte[]> {
        public byte[] deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
            return Base64.getDecoder().decode(json.getAsString());
        }

        public JsonElement serialize(byte[] src, Type typeOfSrc, JsonSerializationContext context) {
            return new JsonPrimitive(Base64.getEncoder().encodeToString(src));
        }
    }
}