## **4. Run Sample Applications**

After installing Hive, Hadoop and Spark successfully, we can now proceed to run some sample applications to see if they are configured appropriately.  We can use Spark Pi and Spark WordCount programs to validate our Spark installation. We can also explore how to run Spark jobs from the command line and Spark shell.

### **4.1 Spark Pi**

 */
package org.apache.maven.model.building;

/**
 * Defines events that the model builder fires during construction of the effective model. When a listener encounters
 * errors while processing the event, it can report these problems via {@link ModelBuildingEvent#getProblems()}.
 * Note: To cope with future extensions to this interface, it is strongly recommended to extend

	// 1.3 Check that svc account info can be queried
	c.assertSvcAccInfoQueryable(ctx, s.adm, accessKey, cr.AccessKey, false)

	// 2. Check that svc account can access the bucket
	c.assertSvcAccS3Access(ctx, s, cr, bucket)

	// 3. Check that svc account can restrict the policy, and that the
	// session policy can be updated.
	c.assertSvcAccSessionPolicyUpdate(ctx, s, s.adm, accessKey, bucket)

import okhttp3.internal.commonParse
import okhttp3.internal.commonToString

/**
 * A Cache-Control header with cache directives from a server or client. These directives set policy
 * on what responses can be stored, and which requests can be satisfied by those stored responses.
 *
 * See [RFC 7234, 5.2](https://tools.ietf.org/html/rfc7234#section-5.2).
 */
class CacheControl internal constructor(
  /**

     * we can override it in our non-null-guaranteeing subtypes to present a better signature to
     * their users.
     *
     * However, the checker *we* use has this special knowledge about `Collection.toArray()` anyway,
     * so in our implementation code, we can rely on that. That's why the expression below
     * type-checks.
     */

We utilize nullness annotations in Java code and somewhat rely on IDE warnings to guide us.
However, the Java code we have is not fully annotated, which causes several consequences:
* IDE warnings can be misleading
* Redundant null checks may increase binary size, hurt performance, and increase cognitive load for readers
* Missing null checks may cause NullPointerException
* Bridging with Kotlin code is polluted with platform types

 *
 * <h4 id="java8">Java 8+ equivalents</h4>
 *
 * If you are using Java version 8 or greater, you should generally use the static methods in {@link
 * Comparator} instead of {@code ComparisonChain}. The example above can be implemented like this:
 *
 * {@snippet :
 * import static java.util.Comparator.comparing;
 * import static java.util.Comparator.nullsLast;
 * import static java.util.Comparator.naturalOrder;
 *
 * ...

 *
 * <ul>
 *   <li>While calls to {@code submit} and {@code submitAsync} return a {@code Future} that can be
 *       cancelled, cancellation never propagates to a task that has started to run -- neither to
 *       the callable itself nor to any {@code Future} returned by an {@code AsyncCallable}.
 *       (However, cancellation can prevent an <i>unstarted</i> task from running.) Therefore, the

{{ template "minio.fullname" . }}-local {{- end }} {{- if eq .Values.service.type "LoadBalancer" }} MinIO can be accessed via port {{ .Values.service.port }} on an external IP address. Get the service external IP address by: kubectl get svc --namespace {{ .Release.Namespace }} -l app={{ template "minio.fullname" . }} Note that the public IP may take a couple of minutes to be available. You can now access MinIO server on http://<External-IP>:9000. Follow the below steps to connect to MinIO server with...

          </excludePackageNames>
          <!-- Ignore some tags that are found in Java 11 sources but not recognized... under -source 8, I think it was? I can no longer reproduce the failure. -->
          <tags>
            <tag>
              <name>apiNote</name>
              <placement>X</placement>
            </tag>
            <tag>