public Flowable<String> getKeys() {
        return getKeysByPattern(null);
    }
@Test
    public void testGetKeys() {
        RKeysRx keys = redisson.getKeys();
        sync(redisson.getBucket("test1").set(1));
        sync(redisson.getBucket("test2").set(1));
        Flowable<String> k = keys.getKeys();
        assertThat(k.blockingIterable()).contains("test1", "test2");
    }