public string NextKey(string afterThisKey)
{
XBucket bucket;
string prefix;
string result = null;
bool found = FindBucketForPrefix(afterThisKey, out bucket, out prefix, false);
if (found)
{
result = bucket.NextKey(afterThisKey);
if (result != null)
{
return(result);
}
}
// otherwise look in the next bucket
string nextprefix = this.tree.NextKey(prefix);
if (nextprefix == null)
{
return(null);
}
byte[] databytes = this.tree[nextprefix];
bucket = new XBucket(this);
bucket.Load(databytes);
if (bucket.Count() < 1)
{
throw new BplusTreeException("empty bucket loaded");
}
return(bucket.FirstKey());
}
public bool FindBucketForPrefix(string key, out XBucket bucket, out string prefix, bool keyIsPrefix)
{
bucket = null;
prefix = key;
if (!keyIsPrefix)
{
prefix = PrefixForByteCount(key, this.PrefixLength);
}
object datathing = this.tree.Get(prefix, "");
if (datathing is byte[])
{
byte[] databytes = (byte[])datathing;
bucket = new XBucket(this);
bucket.Load(databytes);
if (bucket.Count() < 1)
{
throw new BplusTreeException("empty bucket loaded");
}
return(true);
}
return(false); // default
}