### Question:
DownloadListenerBunch implements DownloadListener { @Override public void connectStart(@NonNull DownloadTask task, int blockIndex, @NonNull Map<String, List<String>> requestHeaderFields) { for (DownloadListener listener : listenerList) { listener.connectStart(task, blockIndex, requestHeaderFields); } } DownloadListenerBunch(@NonNull DownloadListener[] listenerList); @Override void taskStart(@NonNull DownloadTask task); @Override void connectTrialStart(@NonNull DownloadTask task,
                                  @NonNull Map<String, List<String>> requestHeaderFields); @Override void connectTrialEnd(@NonNull DownloadTask task, int responseCode,
                                          @NonNull Map<String, List<String>> responseHeaderFields); @Override void downloadFromBeginning(@NonNull DownloadTask task, @NonNull BreakpointInfo info,
                                      @NonNull ResumeFailedCause cause); @Override void downloadFromBreakpoint(@NonNull DownloadTask task, @NonNull BreakpointInfo info); @Override void connectStart(@NonNull DownloadTask task, int blockIndex,
                                       @NonNull Map<String, List<String>> requestHeaderFields); @Override void connectEnd(@NonNull DownloadTask task, int blockIndex, int responseCode,
                                     @NonNull Map<String, List<String>> responseHeaderFields); @Override void fetchStart(@NonNull DownloadTask task, int blockIndex, long contentLength); @Override void fetchProgress(@NonNull DownloadTask task, int blockIndex, long increaseBytes); @Override void fetchEnd(@NonNull DownloadTask task, int blockIndex, long contentLength); @Override void taskEnd(@NonNull DownloadTask task, @NonNull EndCause cause,
                        @Nullable Exception realCause); boolean contain(DownloadListener targetListener); int indexOf(DownloadListener targetListener);  }### Answer:
@Test public void connectStart() throws Exception { listenerBunch.connectStart(task, 1, headerFields); verify(listener1).connectStart(eq(task), eq(1), eq(headerFields)); verify(listener2).connectStart(eq(task), eq(1), eq(headerFields)); }