### Question:
DefaultChannelManager implements ChannelManager { @NotNull @Override public Optional<NetworkChannel> getFirstChannel() { Iterator<NetworkChannel> iterator = this.channels.values().iterator(); return iterator.hasNext() ? Optional.of(iterator.next()) : Optional.empty(); }  @NotNull @Override Optional<NetworkChannel> getChannel(@NotNull String name); @NotNull @Override @UnmodifiableView Collection<NetworkChannel> getNetworkChannels(@NotNull String remoteAddress); @NotNull @Override Optional<NetworkChannel> getFirstChannel(); @NotNull @Override @UnmodifiableView Collection<NetworkChannel> getRegisteredChannels(); @NotNull @Override NetworkChannel createChannel(@NotNull Channel channel); @Override void registerChannel(@NotNull NetworkChannel channel); @Override void unregisterChannel(@NotNull String name);  }### Answer:
@Test @Order(2) void testGetFirstChannel() { Assertions.assertNotNull(this.channelManager.getFirstChannel()); }