title: org/dom4j/DocumentException
body: <p>Good morning every body , </p>
  
  <p>I have java code that alllows me to create an excel file from xml flie.. But it can not create correctly the file, i have this exception that I do not inderstand its meaning :</p>
  
  <pre><code>Exception in thread "main" java.lang.NoClassDefFoundError: org/dom4j/DocumentException
  at org.apache.poi.openxml4j.opc.Package.init(Package.java:145)
  at org.apache.poi.openxml4j.opc.Package.&lt;init&gt;(Package.java:132)
  at org.apache.poi.openxml4j.opc.ZipPackage.&lt;init&gt;(ZipPackage.java:67)
  at org.apache.poi.openxml4j.opc.Package.create(Package.java:271)
  at org.apache.poi.xssf.usermodel.XSSFWorkbook.newPackage(XSSFWorkbook.java:245)
  at org.apache.poi.xssf.usermodel.XSSFWorkbook.&lt;init&gt;(XSSFWorkbook.java:145)
  at escel1.Escel1.main(Escel1.java:104)
  Caused by: java.lang.ClassNotFoundException: org.dom4j.DocumentException
  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)
  </code></pre>
  
  <p>If someone knows what that means , it will be very helpfull for me :) </p>