Very simple Apache-commons configuration example throws NoClassDefFoundError

I'm trying to test a very simple example given in the Apache-commons configuration library user's guide regarding declaring and creating beans. I copied the code in the example almost word by word, and yet I'm getting a NoClassDefFoundError exception. Here is the xml file I'm using - `windowcongif.xml`: ``` <?xml version="1.0" encoding="ISO-8859-1" ?> <config> <gui> <windowManager config-class="test.DefaultWindowManager" closable="false" resizable="true" defaultWidth="400" defaultHeight="250"> </windowManager> </gui> </config> ``` Here is the code in the file `WindowManager.java`: ``` package test; public interface WindowManager {} ``` Here is the code in the file `DefaultWindowManager.java`: ``` package test; public class DefaultWindowManager implements WindowManager { private boolean resizable; private boolean closable; private int defaultWidth; private int defaultHeight; } ``` Here is the code in the file `Main.java`: ``` package test; import org.apache.commons.configuration.ConfigurationException; import org.apache.commons.configuration.XMLConfiguration; import org.apache.commons.configuration.beanutils.BeanDeclaration; import org.apache.commons.configuration.beanutils.BeanHelper; import org.apache.commons.configuration.beanutils.XMLBeanDeclaration; public class Main { public static void main(String[] args) throws ConfigurationException { XMLConfiguration config = new XMLConfiguration("windowconfig.xml"); BeanDeclaration decl = new XMLBeanDeclaration(config, "gui.windowManager"); WindowManager wm = (WindowManager) BeanHelper.createBean(decl); } } ``` Here is the output during runtime: ``` Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/beanutils/PropertyUtils at org.apache.commons.configuration.beanutils.BeanHelper.initProperty(BeanHelper.java:269) at org.apache.commons.configuration.beanutils.BeanHelper.initBeanProperties(BeanHelper.java:229) at org.apache.commons.configuration.beanutils.BeanHelper.initBean(BeanHelper.java:166) at org.apache.commons.configuration.beanutils.DefaultBeanFactory.initBeanInstance(DefaultBeanFactory.java:108) at org.apache.commons.configuration.beanutils.DefaultBeanFactory.createBean(DefaultBeanFactory.java:64) at org.apache.commons.configuration.beanutils.BeanHelper.createBean(BeanHelper.java:336) at org.apache.commons.configuration.beanutils.BeanHelper.createBean(BeanHelper.java:358) at org.apache.commons.configuration.beanutils.BeanHelper.createBean(BeanHelper.java:372) at test.Main.main(Main.java:23) Caused by: java.lang.ClassNotFoundException: org.apache.commons.beanutils.PropertyUtils at java.net.URLClassLoader$1.run(URLClassLoader.java:366) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:423) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at java.lang.ClassLoader.loadClass(ClassLoader.java:356) ... 9 more ``` How do I make this simple example work? I'm using version 1.9 of the commons-configuration package, auto-imported by IntelliJ IDEA after putting the dependency in the `pom.xml` file, and version 1.7.0_17 of java running on Windows 8 64bit.