15 Exercises to Know a Programming Language: Part 3, Libraries, Frameworks, and Mashups

This is the final post in a series of 3 covering 15 exercises that provide a sense of a programming  language's idioms and "feel." For newcomers, if you can't "jump in" and tackle these exercises in a  particular programming language, don't embarrass yourself by claiming to know that language. For more experienced developers, these programs should be tough enough to require problem solving: try to embrace the language's idioms.

The first series of exercises dealt with calculations, the second with data structures. This final series is the fun one: exploiting libraries and unique environmental capabilities.


  1. Write a program that outputs the current date and time to a Web page as a reversed ISO 8601-formatted value (i.e.: "2006-06-16T13:15:30Z" becomes "Z03:51:31T61-60-6002"). Create an XML interface (either POX or WS-*) to the same.

Educational goals of exercise 11:
  "Hello, Web!"

  1. Write a client-side program that can both scrape the above Web page and the XML return and redisplays the date in a different format.

Educational goals of exercise 12:
  HTTP get, string parsing.

  1. Write a daemon program that monitors an email account. When a strongly-encoded email arrives that decrypts to a valid ISO 8601 time, the program sets the system time to that value.

Educational goals of exercise 13:
  Encryption, Email, OS libraries, daemons

  1. Write a program that connects to your mail client, performs a statistical analysis of its contents (see Part 1, Part 2.