Question

So, Redis specify the zrange (and related sorted set commands) as an ORDERED set of results (a list without duplicates perhaps?).

Why then the zrange (and related APIs) on Jedis (Official and Recommended REDIS client) return a Set??? Which has, by definition, no concept of ordering?

That is a direct violation of the semantics of the redis operations.

This is the zrange jedis 2.0.0 implementation:

---

  public Set<byte[]> zrange(final byte[] key, final int start, final int end) {
        checkIsInMulti();
        client.zrange(key, start, end);
        final List<byte[]> members = client.getBinaryMultiBulkReply();
        return new LinkedHashSet<byte[]>(members);
    } 

Jedis contributors, are you planning to fix it?

Answer 1

In version 2.2.0 it will be returning SorteSet, according to https://github.com/xetorthio/jedis/issues/244