title: java - Exception in thread "main" java.lang.NoClassDefFoundError: io/kubernetes/client/openapi/ApiException
body: <p>I've tried to reproduce the <a href="https://github.com/kubernetes-client/java/blob/master/examples/src/main/java/io/kubernetes/client/examples/Example.java" rel="nofollow noreferrer">example in k8s-java</a> in my mini-maven project.
  However, I kept getting into this error - Exception in thread &quot;main&quot; java.lang.NoClassDefFoundError: io/kubernetes/client/openapi/ApiException.
  My maven project is borrowed from <a href="https://maven.apache.org/guides/getting-started/maven-in-five-minutes.html" rel="nofollow noreferrer">maven in 5 minutes</a> and is only changed a few lines.</p>
  <ul>
  <li>App.java</li>
  </ul>
  <pre class="lang-java prettyprint-override"><code>package com.mycompany.app;
  
  import io.kubernetes.client.openapi.ApiClient;
  import io.kubernetes.client.openapi.ApiException;
  import io.kubernetes.client.openapi.Configuration;
  import io.kubernetes.client.openapi.apis.CoreV1Api;
  import io.kubernetes.client.openapi.models.V1Pod;
  import io.kubernetes.client.openapi.models.V1PodList;
  import io.kubernetes.client.util.Config;
  import java.io.IOException;
  
  
  /**
   * A simple example of how to use the Java API
   *
   * &lt;p&gt;Easiest way to run this: mvn exec:java
   * -Dexec.mainClass=&quot;io.kubernetes.client.examples.Example&quot;
   *
   * &lt;p&gt;From inside $REPO_DIR/examples
   */
  public class App {
      public static void main(String[] args) throws IOException, ApiException {
        ApiClient client = Config.defaultClient();
        Configuration.setDefaultApiClient(client);
    
        CoreV1Api api = new CoreV1Api();
        V1PodList list =
            api.listPodForAllNamespaces(null, null, null, null, null, null, null, null, null);
        for (V1Pod item : list.getItems()) {
          System.out.println(item.getMetadata().getName());
        }
      }
    }
  
  </code></pre>
  <ul>
  <li>pom.xml</li>
  </ul>
  <pre class="lang-xml prettyprint-override"><code> &lt;dependencies&gt;
      &lt;dependency&gt;
        &lt;groupId&gt;junit&lt;/groupId&gt;
        &lt;artifactId&gt;junit&lt;/artifactId&gt;
        &lt;version&gt;4.11&lt;/version&gt;
        &lt;scope&gt;test&lt;/scope&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
        &lt;groupId&gt;io.kubernetes&lt;/groupId&gt;
        &lt;artifactId&gt;client-java&lt;/artifactId&gt;
        &lt;version&gt;10.0.0&lt;/version&gt;
      &lt;/dependency&gt;
    &lt;/dependencies&gt;
  </code></pre>
  <ul>
  <li>Commands</li>
  </ul>
  <ol>
  <li><code>mvn clean package</code></li>
  <li><code>java -cp target/my-app-1.0-SNAPSHOT.jar com.mycompany.app.App</code></li>
  </ol>
  <ul>
  <li>Errors</li>
  </ul>
  <pre><code>Error: A JNI error has occurred, please check your installation and try again
  Exception in thread &quot;main&quot; java.lang.NoClassDefFoundError: io/kubernetes/client/openapi/ApiException
          at java.lang.Class.getDeclaredMethods0(Native Method)
          at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)
          at java.lang.Class.privateGetMethodRecursive(Class.java:3048)
          at java.lang.Class.getMethod0(Class.java:3018)
          at java.lang.Class.getMethod(Class.java:1784)
          at sun.launcher.LauncherHelper.validateMainClass(LauncherHelper.java:650)
          at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:632)
  Caused by: java.lang.ClassNotFoundException: io.kubernetes.client.openapi.ApiException
          at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
          at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
          at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:352)
          at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
          ... 7 more
  </code></pre>
  <p>Thanks anyone for the help!</p>