@Test
 public void removeChannel() {
   final InMemoryDataStore store = new InMemoryDataStore();
   store.saveChannel(new DefaultChannel(UUIDUtil.newUAID(), "channel-1", "endpoint/1"));
   assertThat(store.removeChannel("channel-1"), is(true));
   assertThat(store.removeChannel("channel-1"), is(false));
 }
 @Test
 public void saveChannel() {
   final InMemoryDataStore store = new InMemoryDataStore();
   final boolean saved =
       store.saveChannel(new DefaultChannel(UUIDUtil.newUAID(), "channel-1", "endpoint/1"));
   assertThat(saved, is(true));
 }
 @Test
 public void getChannel() throws ChannelNotFoundException {
   final InMemoryDataStore store = new InMemoryDataStore();
   store.saveChannel(new DefaultChannel(UUIDUtil.newUAID(), "channel-1", "endpoint/1"));
   assertThat(store.getChannel("channel-1"), is(notNullValue()));
   assertThat(store.getChannel("channel-1").getChannelId(), equalTo("channel-1"));
   assertThat(store.getChannel("channel-1").getPushEndpoint(), equalTo("endpoint/1"));
 }
 @Test
 public void storeUpdates() {
   final InMemoryDataStore store = new InMemoryDataStore();
   final String uaid = UUIDUtil.newUAID();
   final String channelId1 = UUID.randomUUID().toString();
   store.saveUpdates(updates(update(channelId1, 10L)), uaid);
   final Set<Update> updates = store.getUpdates(uaid);
   assertThat(updates, hasItem(update(channelId1, 10L)));
 }
 @Test
 public void removeUpdate() {
   final InMemoryDataStore store = new InMemoryDataStore();
   final String uaid = UUIDUtil.newUAID();
   final String channelId1 = UUID.randomUUID().toString();
   store.saveUpdates(updates(update(channelId1, 10L)), uaid);
   assertThat(store.removeUpdate(update(channelId1, 10L), uaid), is(true));
   assertThat(store.removeUpdate(update(channelId1, 10L), uaid), is(false));
   assertThat(store.removeUpdate(update(channelId1, 11L), uaid), is(false));
 }
 @Test
 public void removeChannels() throws ChannelNotFoundException {
   final InMemoryDataStore store = new InMemoryDataStore();
   final String uaid1 = UUIDUtil.newUAID();
   final String uaid2 = UUIDUtil.newUAID();
   store.saveChannel(new DefaultChannel(uaid1, "channel-1", "endpoint/1"));
   store.saveChannel(new DefaultChannel(uaid2, "channel-2", "endpoint/2"));
   store.saveChannel(new DefaultChannel(uaid1, "channel-3", "endpoint/3"));
   store.saveChannel(new DefaultChannel(uaid2, "channel-4", "endpoint/4"));
   store.removeChannels(uaid2);
   assertThat(hasChannel("channel-1", store), is(true));
   assertThat(hasChannel("channel-2", store), is(false));
   assertThat(hasChannel("channel-3", store), is(true));
   assertThat(hasChannel("channel-4", store), is(false));
 }