title: Android java.lang.NoClassDefFoundError using JODA libraries
body: <p>I'm stuck from about 2 hours on a problem that i thought it was easy to solve.
  I'm building a custom date-time picker for the android platform and, because of the slowness of the standard java.util.Calendar and java.util.Date classes, i decided to use the JODA library.</p>
  
  <p>Unfortunately i've got no experience with 'JAR' references (forgive me...i come from COM and .NET assemblies world =)...), but i learn some tips on internet but obviously they seems to be wrong...
  These are the steps i took to use the library in my project:</p>
  
  <ol>
  <li>Download the latest JODA library 2.1</li>
  <li>Create the 'lib' folder into my project folder</li>
  <li>Add 'joda-time-2.1.jar' to the 'lib' folder.</li>
  <li>Add the 'joda-time-2.1.jar' library to the build path.</li>
  <li>Add 'joda-time-2.1-javadoc.jar' and 'joda-time-2.1-sources.jar' to the 'lib' folder</li>
  <li>Set the above libraries as 'java source attachements' and 'javadoc location' for the joda-time-2.1 referenced library.</li>
  <li>Use the new library into my code (the ehm ehm 'intelli-sense' and compiler don't throws any error or warning)</li>
  <li>Start debug on real or virtual device.</li>
  </ol>
  
  <p>When it comes to the following line (the first one that uses JODA BTW), debug stops:</p>
  
  <pre><code>DateTime newDate = new DateTime(2012, 5, 3, 12, 0, 0);
  </code></pre>
  
  <p>And returns the following stack trace:</p>
  
  <pre><code>05-03 19:09:14.349: E/AndroidRuntime(4071): java.lang.NoClassDefFoundError: org.joda.time.DateTime
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at it.paganel.droidMessageExport.Control.TimePickerControl.SetTimePart(TimePickerControl.java:83)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at it.paganel.droidMessageExport.Control.TimePickerControl.onClick(TimePickerControl.java:116)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at android.view.View.performClick(View.java:2454)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at android.view.View$PerformClick.run(View.java:9030)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at android.os.Handler.handleCallback(Handler.java:587)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at android.os.Handler.dispatchMessage(Handler.java:92)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at android.os.Looper.loop(Looper.java:123)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at android.app.ActivityThread.main(ActivityThread.java:4641)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at java.lang.reflect.Method.invokeNative(Native Method)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at java.lang.reflect.Method.invoke(Method.java:521)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:870)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:628)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at dalvik.system.NativeStart.main(Native Method)
  05-03 19:09:14.349: E/AndroidRuntime(4071): Caused by: java.lang.ClassNotFoundException: org.joda.time.DateTime in loader dalvik.system.PathClassLoader[/data/app/it.paganel.droidMessageExport-2.apk]
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at java.lang.ClassLoader.loadClass(ClassLoader.java:573)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     at java.lang.ClassLoader.loadClass(ClassLoader.java:532)
  05-03 19:09:14.349: E/AndroidRuntime(4071):     ... 13 more
  </code></pre>
  
  <p>Someone can help me?
  Thanks in advance!</p>