// it.
    executeListener(runnable, executor);
  }

  /**
   * Runs this execution list, executing all existing pairs in the order they were added. However,
   * note that listeners added after this point may be executed before those previously added, and
   * note that the execution order of all listeners is ultimately chosen by the implementations of
   * the supplied executors.
   *

  protected AbstractExecutionThreadService() {}

  /**
   * Start the service. This method is invoked on the execution thread.
   *
   * <p>By default this method does nothing.
   */
  protected void startUp() throws Exception {}

  /**
   * Run the service. This method is invoked on the execution thread. Implementations must respond
   * to stop requests. You could poll for lifecycle changes in a work loop:
   *

    }

    /**
     * Gets the total execution time for the search request in milliseconds.
     *
     * @return the execution time in milliseconds
     */
    public long getExecTime() {
        return execTime;
    }

    /**
     * Sets the total execution time for the search request in milliseconds.
     *
     * @param execTime the execution time in milliseconds
     */

/**
 * Represents the result of a search operation in the rank fusion system.
 *
 * This class encapsulates all the information returned from a search query,
 * including the list of matching documents, total record count, query execution
 * time, facet information, and metadata about the search results.
 */
public class SearchResult {

    /** The list of documents returned by the search query. */

   * given executor at the first call to {@code addListener}. The task must be started by the
   * executor promptly, or else the returned {@code ListenableFuture} may fail to work. The task's
   * execution consists of blocking until the input future is {@linkplain Future#isDone() done}, so
   * each call to this method may claim and hold a thread for an arbitrary length of time. Use of

import org.apache.maven.artifact.resolver.ArtifactResolutionResult;
import org.apache.maven.artifact.resolver.ResolutionErrorHandler;
import org.apache.maven.execution.DefaultMavenExecutionRequest;
import org.apache.maven.execution.DefaultMavenExecutionResult;
import org.apache.maven.execution.MavenSession;
import org.apache.maven.impl.DefaultArtifact;
import org.apache.maven.impl.DefaultArtifactCoordinatesFactory;

    // Execution Type Constants
    // ============================================================

    /** Execution type for crawler operations. */
    public static final String EXECUTE_TYPE_CRAWLER = "crawler";

    /** Execution type for thumbnail operations. */
    public static final String EXECUTE_TYPE_THUMBNAIL = "thumbnail";

    /** Execution type for Python script operations. */

    /**
     * Returns the input stream to be used for the Maven execution.
     * If not set, {@link System#in} will be used by default.
     *
     * @return the input stream, or null if not set
     */
    @Nullable
    InputStream stdIn();

    /**
     * Returns the output stream to be used for the Maven execution.
     * If not set, {@link System#out} will be used by default.
     *

   * The listener will run when the {@code Future}'s computation is {@linkplain Future#isDone()
   * complete} or, if the computation is already complete, immediately.
   *
   * <p>There is no guaranteed ordering of execution of listeners, but any listener added through
   * this method is guaranteed to be called once the computation is complete.
   *
   * <p>Exceptions thrown by a listener will be propagated up to the executor. Any exception thrown

     *
     * @return the current project or {@code empty()} if not applicable
     */
    @Nonnull
    Optional<Project> getProject();

    /**
     * Gets the current mojo execution (if any).
     *
     * @return the current mojo execution or {@code empty()} if not applicable
     */
    @Nonnull
    Optional<MojoExecution> getMojoExecution();

    /**
     * Gets the exception that caused the event (if any).
     *