1. Connecting to Web Services Sean Sullivan Android Dev Camp Amsterdam 8 January 2009

2. +

3. HTTP XML JSON OAuth

4. HTTP request XML response

5. http://code.google.com/p/jreeagle

6. jreeagle uses: HttpClient API XStream OAuth Java library

7. An open protocol to allow secure API authorization in a simple and standard method from desktop and web applications

8. use OAuth to access protected data your application needs to obtain an access token from the service provider service provider will issue access token after the user grants permission

9. + http://code.google.com/p/oauth

10. + jreeagle http://code.google.com/p/jreeagle/wiki/Android jpoco http://code.google.com/p/jpoco/wiki/Android

11. + HTTP Option 1 java.net.URL java.net.HttpURLConnection Option 2 HttpClient 4.0 API

12. HttpClient 4.0 API org.apache.http.client.HttpClient org.apache.http.impl.client.DefaultHttpClient

13. HttpClient 4.0 API org.apache.http.client.methods.HttpGet org.apache.http.client.methods.HttpPost org.apache.http.client.methods.HttpPut org.apache.http.client.methods.HttpDelete

14. HttpClient 4.0 API org.apache.http.HttpResponse org.apache.http.StatusLine org.apache.http.HttpEntity org.apache.http.utils.EntityUtils

15. HttpClient programming HTTP response status code I/O exceptions timeouts gzip?

16. HttpClient programming synchronous invocation public HttpResponse execute(HttpUriRequest request) asynchronous invocation public HttpResponse execute(HttpUriRequest request, ResponseHandler handler)

17. Android UI thread user clicks on button onClick listener Dont block the UI thread! Tip: use java.lang.Runnable

18. Response formats XML JSON RSS, Atom other

19. XML processing org.w3c.dom package (DOM) org.xml.sax package (SAX) org.xmlpull package (XPP3) XStream JDOM Apache XmlBeans * * does not work on Android 1.0

20. JSON processing org.json package Google GSON library * XStream + Jettison * json-lib * * does not work on Android 1.0

21. Client libraries code.google.com/p/jreeagle code.google.com/p/jpoco code.google.com/p/meetup-java-client code.google.com/p/upcoming-java-client code.google.com/p/gdata-java-client ickrj.sourceforge.net

22. Conclusion HttpClient API use XStream for XML processing use org.json package for JSON processing OAuth has a learning curve OAuth affects user experience

23. Thank you

24. Resources http://code.google.com/android/documentation.html http://hc.apache.org/httpcomponents-client http://code.google.com/p/oauth http://xstream.codehaus.org