Beginners Problem - Class Definition Not Found

From:

William Colls <william.colls@rogers.com>

Newsgroups:

comp.lang.java.help

Date:

Fri, 22 Jul 2011 10:47:18 -0400

Message-ID:

<j0c2h9$c93$1@theodyn.ncf.ca>

Environment:
    Kubuntu 10.04 patched up to date 64 bit.
    java version 1.6.0_24
    Netbeans IDE 6.8

I am trying to set up a connection to my google calendar, using the
information provided at the Google API web site. I have the following
program, which builds correctly with the Netbeans IDE 6.8

If I understand the error message correctly, it is saying that it can't
find a class definition for com.google.gdata.wireformats.AltRegistry.
This class appears to be defined in gdata-core-1.0.jar. This file is in
the library listing for Netbeans.

At runtime, the CLASSPATH variable points to the folder that contains
all the .jar files that are referenced by the import statements.

So why doesn't the program find the class definition?

// begin my program

package google;

import com.google.gdata.client.*;
import com.google.gdata.client.calendar.*;
import com.google.gdata.data.*;
import com.google.gdata.data.acl.*;
import com.google.gdata.data.calendar.*;
import com.google.gdata.data.extensions.*;
import com.google.gdata.util.*;

import java.net.*;
import java.io.*;

import sample.util.*;

public class Calender {

   public static void main(String[] args) {

     CalendarService myService = null;
     URL feedUrl = null;
     CalendarFeed resultFeed = null;

     try {
       myService = new CalendarService("exampleCo-exampleApp-1.0");
       myService.setUserCredentials("root@gmail.com", "pa$$word");
     }
     catch(AuthenticationException ae) {
       System.out.println("Authentication Exception: " +
ae.getMessage());
     }

     try {
       feedUrl = new

URL("http://www.google.com/calendar/feeds/default/allcalendars/full");
       resultFeed = myService.getFeed(feedUrl, CalendarFeed.class);
     }

     catch(MalformedURLException mue) {
       System.out.println("URL Exception: " + mue.getMessage());
     }

     catch(ServiceException se) {
       System.out.println("Service Exception: " + se.getMessage());
     }
     catch (java.io.IOException ioe) {
       System.out.println("IO Exception: " + ioe.getMessage());
     }

     System.out.println("Your calendars:");
     System.out.println();

     for (int i = 0; i < resultFeed.getEntries().size(); i++) {
       CalendarEntry entry = resultFeed.getEntries().get(i);
       System.out.println("\t" + entry.getTitle().getPlainText());
     }
   }
}

// end my program

However when I try to run it I get the following error message:

Exception in thread "main" java.lang.NoClassDefFoundError:
com/google/common/collect/Maps
at com.google.gdata.wireformats.AltRegistry.<init>(AltRegistry.java:118)
at com.google.gdata.wireformats.AltRegistry.<init>(AltRegistry.java:100)
at com.google.gdata.client.Service.<clinit>(Service.java:555)
at google.Calender.main(Calender.java:27)
Caused by: java.lang.ClassNotFoundException: com.google.common.collect.Maps
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
.... 4 more

I recognize that the credentials provided in the listing above are
wrong. I will put the correct ones in when I get this thing to run.

Thanks for your patience with a beginner in the wonderful world of java.