### **4.1 Spark Pi**

Test the Spark installation by running the following compute intensive example, which calculates pi by “throwing darts” at a circle. The program generates points in the unit square ((0,0) to (1,1)) and counts how many points fall within the unit circle within the square. The result approximates pi.

Follow these steps to run the Spark Pi example:

- Login as user **‘spark’**.

	if err := DB.Where("name = ?", "first_or_create_pet1").First(&Pet{}).Error; err != nil {
		t.Errorf("has many association should be saved")
	}

	if err := DB.Where("number = ?", "1231231231").First(&Account{}).Error; err != nil {
		t.Errorf("belongs to association should be saved")
	}
}

    /** Executor service for concurrent search operations across multiple searchers */
    protected ExecutorService executorService;

    /** Size of the window for rank fusion processing, determines how many results to consider */
    protected int windowSize;

    /** Set of available searcher names that can be used for search processing */
    protected Set<String> availableSearcherNameSet;

    /**

import java.util.function.Function;
import java.util.stream.Collector;
import java.util.stream.Collectors;
import org.jspecify.annotations.Nullable;

/**
 * A {@link Map} whose contents will never change, with many other important properties detailed at
 * {@link ImmutableCollection}.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *

Probablemente puedas saltarte esto.

Estos son detalles muy técnicos de cómo funciona **FastAPI** en su interior.

Si tienes bastante conocimiento técnico (coroutines, hilos, bloqueo, etc.) y tienes curiosidad sobre cómo FastAPI maneja `async def` vs `def` normal, adelante.

///

### Funciones de *path operation*

    assertTrue(Sets.intersection(cache.asMap().keySet(), removalNotifications.keySet()).isEmpty());
    threadPool.shutdown();
    threadPool.awaitTermination(300, SECONDS);
  }

  /**
   * Calls get() repeatedly from many different threads, and tests that all of the removed entries
   * (removed because of size limits or expiration) trigger appropriate removal notifications.
   */
  @GwtIncompatible // QueuingRemovalListener

    assertTrue(Sets.intersection(cache.asMap().keySet(), removalNotifications.keySet()).isEmpty());
    threadPool.shutdown();
    threadPool.awaitTermination(300, SECONDS);
  }

  /**
   * Calls get() repeatedly from many different threads, and tests that all of the removed entries
   * (removed because of size limits or expiration) trigger appropriate removal notifications.
   */
  @GwtIncompatible // QueuingRemovalListener

 *   <li>{@link Files#createTempDir()} is tested in {@link FilesCreateTempDirTest}.
 * </ul>
 *
 * @author Chris Nokleberg
 */

@SuppressWarnings("InlineMeInliner") // many tests of deprecated methods
@NullUnmarked
public class FilesTest extends IoTestCase {

  @AndroidIncompatible // suites, ByteSourceTester (b/230620681)
  public static TestSuite suite() {

 *       operation that causes a key to have zero associated values has the effect of
 *       <i>removing</i> that key from the multimap.
 *   <li>The total entry count is available as {@link #size}.
 *   <li>Many complex operations become easier; for example, {@code
 *       Collections.min(multimap.values())} finds the smallest value across all keys.
 * </ul>
 *
 * <h3>Implementations</h3>
 *
 * <ul>

       *
       * - ReschedulableCallable has a reference back to its enclosing CustomScheduler. (It needs it
       *   so that it can call getNextSchedule).
       *
       * Maybe there is a way to avoid this cycle. But we think the cycle is safe enough to ignore:
       * Each task is retained for only as long as it is running -- so it's retained only as long as