android rest

1. https://code.tutsplus.com/tutorials/android-from-scratch-using-rest-apis--cms-27117
2. https://code.tutsplus.com/tutorials/a-beginners-guide-to-http-and-rest--net-16340
3. https://dzone.com/articles/creating-a-simple-android-rest-client-using-http-r
4.