Get a exception of "error connecting with login URI" when running Google Data's example

When I run the example CalendarFeedDemo in the JAVA package of the Google Data API client library, I've encounterd a exception like this

java -classpath "classes:lib/*" CalendarFeedDemo myaddr@gmail.com mypassed
http://www.google.com/calendar/feeds/myaddr@gmail.com
com.google.gdata.util.AuthenticationException: Error connecting with login URI
    at com.google.gdata.client.GoogleAuthTokenFactory.getAuthToken(GoogleAuthTokenFactory.java:489)
    at com.google.gdata.client.GoogleAuthTokenFactory.setUserCredentials(GoogleAuthTokenFactory.java:346)
    at com.google.gdata.client.GoogleService.setUserCredentials(GoogleService.java:362)
    at com.google.gdata.client.GoogleService.setUserCredentials(GoogleService.java:317)
    at CalendarFeedDemo.main(CalendarFeedDemo.java:261)
Caused by: java.net.SocketException: Network is unreachable
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333)
    at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195)
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
    at java.net.Socket.connect(Socket.java:525)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:550)
    at com.sun.net.ssl.internal.ssl.BaseSSLSocket开发者_如何学运维Impl.connect(BaseSSLSocketImpl.java:141)
    at sun.net.NetworkClient.doConnect(NetworkClient.java:163)
    at sun.net.www.http.HttpClient.openServer(HttpClient.java:394)
    at sun.net.www.http.HttpClient.openServer(HttpClient.java:529)
    at sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:272)
    at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:329)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:172)
    at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:801)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:158)
    at sun.net.www.protocol.http.HttpURLConnection.getOutputStream(HttpURLConnection.java:904)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.getOutputStream(HttpsURLConnectionImpl.java:230)
    at com.google.gdata.client.GoogleAuthTokenFactory.makePostRequest(GoogleAuthTokenFactory.java:547)
    at com.google.gdata.client.GoogleAuthTokenFactory.getAuthToken(GoogleAuthTokenFactory.java:487)
    ... 4 more

I cannot understand why there is a such exception. Please help me.

From the Network is unreachable, I'd say a connection error : either Google was unreachable (which is not very probable), either your internet connection had a problem.

If you're behind a proxy you need to tell java about it like this:

java -DproxyHost=<proxy host> -DproxyPort=<proxy port> -classpath %cPath% com.googlecode.syncnotes2google.SyncNotes2Google

I had to use this when using the syncnotes2google application.