## **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**

     */
    @Nonnull
    Optional<Boolean> showVersion();

    /**
     * Indicates whether to run in quiet mode.
     *
     * @return an {@link Optional} containing the boolean flag, or empty if not set
     */
    @Nonnull
    Optional<Boolean> quiet();

    /**
     * Indicates whether to run in verbose mode.
     *
     * @return an {@link Optional} containing the boolean flag, or empty if not set
     */

            if (n <= 0) {
                break;
            }
            i += n;
        }

        return i;
    }

    /* state values
     * 0 - not connected
     * 1 - connecting
     * 2 - run connected
     * 3 - connected
     * 4 - error
     */
    int state = 0;

    String name = "Transport" + id++;
    Thread thread;
    TransportException te;

/** A basic HTTP/2 server that serves the contents of a local directory.  */
class Http2Server(
  private val baseDirectory: File,
  private val sslSocketFactory: SSLSocketFactory,
) : Http2Connection.Listener() {
  private fun run() {
    val serverSocket = ServerSocket(8888)
    serverSocket.reuseAddress = true
    while (true) {
      var socket: Socket? = null
      try {
        socket = serverSocket.accept()

/** Replacements for JUnit's {@code assertThrows} that work under GWT/J2CL. */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
final class ReflectionFreeAssertThrows {
  interface ThrowingRunnable {
    void run() throws Throwable;
  }

  interface ThrowingSupplier {
    @Nullable Object get() throws Throwable;
  }

  @CanIgnoreReturnValue
  static <T extends Throwable> T assertThrows(

}

// RuntimeClass defines a class of container runtime supported in the cluster.
// The RuntimeClass is used to determine which container runtime is used to run
// all containers in a pod. RuntimeClasses are manually defined by a
// user or cluster provisioner, and referenced in the PodSpec. The Kubelet is
// responsible for resolving the RuntimeClassName reference before running the

# Test Guide

```bash
cd tests
# prepare test databases
docker-compose up

# run all tests
./tests_all.sh

	// Exec with default settings...
	resetCompressEncryption()
	t.Run("default", func(t *testing.T) {
		fn(t, nil, MakeBucketOptions{})
	})
	t.Run("default+versioned", func(t *testing.T) {
		fn(t, nil, MakeBucketOptions{VersioningEnabled: true})
	})

	t.Run("compressed", func(t *testing.T) {
		fn(t, func() {
			resetCompressEncryption()

import uvicorn
from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def root():
    a = "a"
    b = "b" + a
    return {"hello world": b}


if __name__ == "__main__":

  private final int port;

  public SampleServer(SSLContext sslContext, String root, int port) {
    this.sslContext = sslContext;
    this.root = root;
    this.port = port;
  }

  public void run() throws IOException {
    MockWebServer server = new MockWebServer();
    server.useHttps(sslContext.getSocketFactory(), false);
    server.setDispatcher(this);
    server.start(port);
  }