### Question:
DownloadListener4 implements DownloadListener,
        Listener4Assist.Listener4Callback, ListenerAssist { @Override public void setAlwaysRecoverAssistModelIfNotSet(boolean isAlwaysRecoverAssistModel) { assist.setAlwaysRecoverAssistModelIfNotSet(isAlwaysRecoverAssistModel); } DownloadListener4(Listener4Assist assist);  DownloadListener4(); void setAssistExtend(@NonNull Listener4Assist.AssistExtend assistExtend); @Override boolean isAlwaysRecoverAssistModel(); @Override void setAlwaysRecoverAssistModel(boolean isAlwaysRecoverAssistModel); @Override void setAlwaysRecoverAssistModelIfNotSet(boolean isAlwaysRecoverAssistModel); @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 final void downloadFromBeginning(@NonNull DownloadTask task,
                                                      @NonNull BreakpointInfo info,
                                                      @NonNull ResumeFailedCause cause); @Override final void downloadFromBreakpoint(@NonNull DownloadTask task,
                                                       @NonNull BreakpointInfo info); @Override void fetchStart(@NonNull DownloadTask task, int blockIndex, long contentLength); @Override final void fetchProgress(@NonNull DownloadTask task, int blockIndex,
                                    long increaseBytes); @Override void fetchEnd(@NonNull DownloadTask task, int blockIndex, long contentLength); @Override final void taskEnd(@NonNull DownloadTask task, @NonNull EndCause cause,
                              @Nullable Exception realCause);  }### Answer:
@Test public void setAlwaysRecoverAssistModelIfNotSet() { listener4.setAlwaysRecoverAssistModelIfNotSet(true); verify(assist).setAlwaysRecoverAssistModelIfNotSet(eq(true)); listener4.setAlwaysRecoverAssistModelIfNotSet(false); verify(assist).setAlwaysRecoverAssistModelIfNotSet(eq(false)); }