Added MurmureHash as sharding algo.

src/main/java/redis/clients/util/Sharded.java

@@ -10,15 +10,19 @@ import java.util.TreeMap;
 
 public abstract class Sharded<T> {
     public static final int DEFAULT_WEIGHT = 1;
-    private static MessageDigest md5 = null; // avoid recurring construction
     private TreeMap<Long, ShardInfo> nodes;
     private int totalWeight;
     private Map<ShardInfo, T> resources;
+    private Hashing algo = Hashing.MD5;
 
     public Sharded(List<ShardInfo> shards) {
 	initialize(shards);
     }
 
+    public Sharded(List<ShardInfo> shards, Hashing algo) {
+	initialize(shards);
+    }
+
     private void initialize(List<ShardInfo> shards) {
 	nodes = new TreeMap<Long, ShardInfo>();
 	resources = new HashMap<ShardInfo, T>();
@@ -62,21 +66,7 @@ public abstract class Sharded<T> {
     }
 
     private Long calculateHash(String key) {
-	if (md5 == null) {
-	    try {
-		md5 = MessageDigest.getInstance("MD5");
-	    } catch (NoSuchAlgorithmException e) {
-		throw new IllegalStateException("++++ no md5 algorythm found");
-	    }
-	}
-
-	md5.reset();
-	md5.update(key.getBytes());
-	byte[] bKey = md5.digest();
-	long res = ((long) (bKey[3] & 0xFF) << 24)
-		| ((long) (bKey[2] & 0xFF) << 16)
-		| ((long) (bKey[1] & 0xFF) << 8) | (long) (bKey[0] & 0xFF);
-	return res;
+	return algo.hash(key);
     }
 
     private Long findPointFor(Long hashK) {