title: Java Eclipse ClassNotFoundException after importing external JARs
body: <p>I'm getting a ClassNotFoundException when I try to execute the following code:</p>
  
  <pre><code>import org.apache.commons.text.WordUtils;
  
  public class CapitalizeFirstLetters {
  
      public static void main(String[] args) {
          String str="this is a test";
          str=WordUtils.capitalizeFully(str);
          System.out.println(str);
  
      }
  
  }
  </code></pre>
  
  <p>I'm new to importing libraries in Java. Here is what my Package Explorer and Build Path look like (I closely followed advice from other people asking similar questions). </p>
  
  <p><a href="https://i.stack.imgur.com/VsG5j.png" rel="nofollow noreferrer">Project Explorer</a> , 
  <a href="https://i.stack.imgur.com/x9UlJ.png" rel="nofollow noreferrer">Java Build Path</a></p>
  
  <p>and here is the error text:</p>
  
  <pre><code>Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/lang3/StringUtils
      at org.apache.commons.text.WordUtils.capitalizeFully(WordUtils.java:494)
      at org.apache.commons.text.WordUtils.capitalizeFully(WordUtils.java:464)
      at CapitalizeFirstLetters.main(CapitalizeFirstLetters.java:7)
  Caused by: java.lang.ClassNotFoundException: org.apache.commons.lang3.StringUtils
      at java.net.URLClassLoader.findClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      ... 3 more
  </code></pre>
  
  <p>Can anyone please help me with this? I cannot find the answer for this problem in Eclipse anywhere online. So far I have tried: deleting everything and starting over.</p>
  
  <p>Thank you! </p>