ApiResponseHandler.java

package org.sana.net.http.handler;

import java.io.IOException;
import java.lang.reflect.Type;

import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.ResponseHandler;
import org.apache.http.util.EntityUtils;

import com.google.gson.FieldNamingPolicy;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonSyntaxException;

import org.sana.net.Response;
import org.sana.net.ResponseException;

public abstract class ApiResponseHandler<T> implements ResponseHandler<T>{

    final static Gson gson = new GsonBuilder()
        .setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES)
        .setDateFormat("yyyy-MM-dd'T'HH:mm:ss")
        .create();

    public abstract Type getType();

    @Override
    public T handleResponse(HttpResponse response)
            throws ClientProtocolException, IOException {
        String json = EntityUtils.toString(response.getEntity());
        Type type = getType();
        try{
            return gson.fromJson(json, type);
        } catch (JsonSyntaxException e){
            throw new ResponseException(json, e);
        }
    }

    public static <K> K fromJson(String json, Type typeOf){
        return gson.fromJson(json, typeOf);
    }

}