## **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**

func TestScanRune(t *testing.T) {
	for n, test := range scanTests {
		buf := strings.NewReader(test)
		s := NewScanner(buf)
		s.Split(ScanRunes)
		var i, runeCount int
		var expect rune
		// Use a string range loop to validate the sequence of runes.
		for i, expect = range test {
			if !s.Scan() {
				break
			}
			runeCount++
			got, _ := utf8.DecodeRune(s.Bytes())
			if got != expect {

	return env.Get("MESOS_CONTAINER_NAME", "") != ""
}

// IsKubernetes returns true if minio is running in kubernetes.
func IsKubernetes() bool {
	// Kubernetes env used to validate if we are
	// indeed running inside a kubernetes pod
	// is KUBERNETES_SERVICE_HOST
	// https://github.com/kubernetes/kubernetes/blob/master/pkg/kubelet/kubelet_pods.go#L541

github.com/envoyproxy/go-control-plane/ratelimit v0.1.0/go.mod h1:Wk+tMFAFbCXaJPzVVHnPgRKdUdwW/KdbRt94AzgRee4=
github.com/envoyproxy/protoc-gen-validate v1.2.1 h1:DEo3O99U8j4hBFwbJfrz9VtgcDfUKS7KJ7spH3d86P8=
github.com/envoyproxy/protoc-gen-validate v1.2.1/go.mod h1:d/C80l/jxXLdfEIhX1W2TmLfsJ31lvEjwamM4DxlWXU=
github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f h1:Y/CXytFA4m6baUTXGLOoWe4PQhGxaX0KpnayAqC48p4=

            } else {
              return Integer.compare(m1.getParameterTypes().length, m2.getParameterTypes().length);
            }
          }
        });
  }

  /** Validates that the given method's signature meets all of our assumptions. */
  private static void validateMethod(Method method) {
    String desc = method.toString();

    assertTrue(desc, isAnyEnter(method) || isWaitFor(method));

0.5rem;\n  margin-top: 0.1rem;\n  font-size: 0.875rem;\n  color: #fff;\n  background-color: var(--bs-success);\n  border-radius: var(--bs-border-radius);\n}\n\n.was-validated :valid ~ .valid-feedback,\n.was-validated :valid ~ .valid-tooltip,\n.is-valid ~ .valid-feedback,\n.is-valid ~ .valid-tooltip {\n  display: block;\n}\n\n.was-validated .form-control:valid, .form-control.is-valid {\n  border-color: var(--bs-form-valid-border-color);\n  padding-right: calc(1.5em + 0.75rem);\n  background-image: u...

			break
		}
		cumulativeSum += size
		encPartSize, _ := sio.EncryptedSize(uint64(size))
		encCumulativeSum += int64(encPartSize)
	}
	// partStart is always found in the loop above,
	// because off is validated.

	sseDAREEncPackageBlockSize := int64(SSEDAREPackageBlockSize + SSEDAREPackageMetaSize)
	startPkgNum := (off - cumulativeSum) / SSEDAREPackageBlockSize

	// Now we can calculate the number of bytes to skip

	if group == "" {
		return updatedAt, errInvalidArgument
	}

	cache := store.lock()
	defer store.unlock()

	// Validate that all members exist.
	for _, member := range members {
		u, ok := cache.iamUsersMap[member]
		if !ok {
			return updatedAt, errNoSuchUser
		}
		cr := u.Credentials

	if idx >= len(p.Pools) {
		// We don't really know if the pool is suspended or not, since it doesn't exist.
		return false
	}
	return p.Pools[idx].Decommission != nil
}

func (p *poolMeta) validate(pools []*erasureSets) (bool, error) {
	type poolInfo struct {
		position     int
		completed    bool
		decomStarted bool // started but not finished yet
	}

	rememberedPools := make(map[string]poolInfo)

	// This call should never be over the network, this is always
	// a cached value - caller should make sure to use this
	// function on a fresh disk or make sure to look at the error
	// from a different networked call to validate the GetDiskID()
	return *client.diskID.Load(), nil
}

func (client *storageRESTClient) SetDiskID(id string) {
	client.diskID.Store(&id)
}