### Question:
CouchDBDataStore implements DataStore { @Override public void savePrivateKeySalt(final byte[] salt) { final byte[] privateKeySalt = getPrivateKeySalt(); if (privateKeySalt.length == 0) { final Map<String, String> map = new HashMap<String, String>(2); map.put(TYPE_FIELD, Views.SERVER.viewName()); map.put("salt", new String(salt, UTF_8)); db.create(map); } } CouchDBDataStore(final String url, final String dbName); @Override void savePrivateKeySalt(final byte[] salt); @Override byte[] getPrivateKeySalt(); @Override boolean saveChannel(final Channel channel); @Override Channel getChannel(final String channelId); @Override void removeChannels(final String uaid); @Override void removeChannels(final Set<String> channelIds); @Override Set<String> getChannelIds(final String uaid); @Override String updateVersion(final String endpointToken, final long version); @Override String saveUnacknowledged(final String channelId, final long version); @Override Set<Ack> getUnacknowledged(final String uaid); @Override Set<Ack> removeAcknowledged(final String uaid, final Set<Ack> acked);  }### Answer:
@Test public void savePrivateKeySalt() { final byte[] salt = "some private salt".getBytes(); datastore.savePrivateKeySalt(salt); assertThat(datastore.getPrivateKeySalt(), equalTo(salt)); }