@Override
  public Router getRouter() {
    return new PerfRouter(perfConfig, perfRouterMetrics);
  }
Creates an instance of PerfRouterFactory.
@param verifiableProperties the in-memory properties for constructing configurations.
@param clusterMap the {@link ClusterMap} whose {@link MetricRegistry} needs to be used.
@param notificationSystem the {@link NotificationSystem} to use (can be {@code null}).
@param sslFactory the {@link SSLFactory} to use (can be {@code null}).
@param accountService the {@link AccountService} to use. Can be {@code null}.
@throws IllegalArgumentException if any of the required arguments are null.
ambry-tools/src/main/java/com/github/ambry/tools/perf/rest/PerfRouterFactory.java