Computer Science 397 Database Programming

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Computer Science 397Database Programming

• Chapter 17 Web Services

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Alsos Search for Niels Bohr
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AtomicArchive.Com Article on Niels Bohr
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AtomicArchive.Com Article on Niels Bohr (cont.)
Produces Alsos Search
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Alsos Search for Niels Bohr
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A specific reference
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Thats 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.

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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.

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What if we wanted to provide this(cont.)

• We would need a platform independent means of
  sharing data
• Thats exactly what XML is all about its text
  based, marked up data.
• Web service software component that you call
  over the web.
• Accepts and returns XML data

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Example Google Service
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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 lt 20 i 10) //
get first 20 hits total result
google.doGoogleSearch("4a8/TvZQFHID0WIWnL1CMmMx0sN
qhG8H", this.txtSearch.get_Text(), i, 10,
false, "", false, "", "", "") for (int j
0 jlt result.resultElements.length j)
re result.resultElementsj
this.lstURLs.get_Items().Add(re.URL)
this.lstURLs.Refresh() //for-n-hits
this.lblHits.set_Text( String.valueOf(result.esti
matedTotalResultsCount) ) MessageBox.Show("Sea
rch complete, first 20 hits are shown!")
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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.Na
vigate(this.lstURLs.get_Text(), a, b, c, d)
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Terra Service
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Stock Ticker