Computer Science 101

1. Computer Science 101 Web Services

2. Alsos Search for Niels Bohr

3. AtomicArchive.Com Article on Niels Bohr

4. AtomicArchive.Com Article on Niels Bohr (cont.) Produces Alsos Search

5. Alsos Search for Niels Bohr

6. A specific reference

7. That’s what they get, not what they want! • We are providing them with a mechanism, “dynamic links”, that enable them to do “live” searches into Alsos – not just link to the Alsos home page, but … • The user ends up in Alsos site, not Atomic Archives. • They would like a way to get data (annotations) from Alsos that they could format within their pages.

8. What if we wanted to provide this: • Suppose we wanted to provide a mechanism for developers to get data from us for use on their web pages. • We would not want them to access our database with SQL statements • Might change database • Want control of the kind of data we let them have • Would not want to restrict to platform, .NET, Linux, etc.

9. What if we wanted to provide this:(cont.) • We would need a platform independent means of sharing data • That’s exactly what XML is all about – it’s text based, marked up data. • Web service – software component that you call over the web. • Accepts and returns XML data

10. The Big Picture • Just like HTML provides a standard way for marking up text for web page display, XML provides a standard way for marking up data. • Web services then provide a standard way for programs to pass this data back and forth to each other.

11. Example – Google Service

12. Search Button private void btnSearch_Click (Object sender, System.EventArgs e) { GoogleSearchResult result = null; GoogleSearchService google; ResultElement re; google = new GoogleSearchService(); this.lstURLs.get_Items().Clear(); for (int i = 0; i < 20; i += 10) // get first 20 hits total { result = google.doGoogleSearch("4a8/TvZQFHID0WIWnL1CMmMx0sNqhG8H", this.txtSearch.get_Text(), i, 10, false, "", false, "", "", ""); for (int j = 0; j< result.resultElements.length; j++) { re = result.resultElements[j]; this.lstURLs.get_Items().Add(re.URL); } this.lstURLs.Refresh(); }//for-n-hits this.lblHits.set_Text( String.valueOf(result.estimatedTotalResultsCount) ); MessageBox.Show("Search complete, first 20 hits are shown!"); }

13. Item Selected private void lstURLs_SelectedIndexChanged (Object sender, System.EventArgs e) { java.lang.Object a, b, c, d; a = b = c = d = null; // optional parameters // navigate to selected site! this.axWebBrowser1.Navigate(this.lstURLs.get_Text(), a, b, c, d); }

14. Terra Service

15. Stock Ticker

16. Movie Theaters

17. Xmethods.net

18. Movie Service

19. Movie Service Description

20. Movie – Code for Find Button

21. Movie – Code for Theater Selection

22. Industry Scenario • Suppose we have a huge industrial manufacturing company. • The parts we need are supplied by a number of different suppliers. • At a given time we may prefer one supplier over the others based on • Current price they offer • Adequacy of their inventory relative to our needs.

23. Industry Scenario (cont.) • Assuming that all of these suppliers provide web services for our use, our decision and purchase could be automated: • Our inventory/purchasing program could communicate our needs to all of the supplier web services and receive their price and inventory information • Based on these results, our program could choose the lowest price among suppliers with acceptable inventories.