DEMO for APNS written by Java
Apple Official document: https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/APNSOverview.html
https://www.zhihu.com/question/20049505 http://blog.csdn.net/shenjie12345678/article/details/41120637 http://www.cocoachina.com/bbs/read.php?tid-123567.html
https://help.apple.com/xcode/mac/current/#/dev54d690a66 https://help.apple.com/xcode/mac/current/#/dev11b059073