In Swift 3.0 Apple removed ‘NS’ prefix and made everything simple. Below is the way to get hour, minute and second from ‘Date’ class (NSDate alternate)
let date = Date()
let calendar = Calendar.current
let hour = calendar.component(.hour, from: date)
let minutes = calendar.component(.minute, from: date)
let seconds = calendar.component(.second, from: date)
print("hours = \(hour):\(minutes):\(seconds)")
Like these you can get era, year, month, date etc. by passing corresponding.