From 726c3151b67c194d84c22e2e80fd3099249eecb7 Mon Sep 17 00:00:00 2001
From: Marcos Nils <marcosnils@gmail.com>
Date: Sun, 8 Dec 2013 01:08:14 -0300
Subject: [PATCH] Add RedisSlot helper to calculate key slot

---
 .../clients/jedis/tests/JedisClusterTest.java | 21 +++++++++++++---
 .../clients/jedis/tests/utils/RedisSlot.java  | 25 +++++++++++++++++++
 2 files changed, 43 insertions(+), 3 deletions(-)
 create mode 100644 src/test/java/redis/clients/jedis/tests/utils/RedisSlot.java

diff --git a/src/test/java/redis/clients/jedis/tests/JedisClusterTest.java b/src/test/java/redis/clients/jedis/tests/JedisClusterTest.java
index 68ad4eb..6e4a7cf 100644
--- a/src/test/java/redis/clients/jedis/tests/JedisClusterTest.java
+++ b/src/test/java/redis/clients/jedis/tests/JedisClusterTest.java
@@ -12,6 +12,7 @@ import redis.clients.jedis.Jedis;
 import redis.clients.jedis.JedisCluster;
 import redis.clients.jedis.Pipeline;
 import redis.clients.jedis.exceptions.JedisMovedDataException;
+import redis.clients.jedis.tests.utils.RedisSlot;
 
 public class JedisClusterTest extends Assert {
     private Jedis node1;
@@ -68,8 +69,22 @@ public class JedisClusterTest extends Assert {
     	jc.get("foo");
     }
 
-    @Test
-    public void ask() {
-	//TODO: needs to implement
+//    @Test
+//    public void ask() {
+//    	JedisCluster jc = new JedisCluster(new HashSet<HostAndPort>(HostAndPortUtil.getClusterServers()));
+//    	jc.set("foo", "bar");
+//    	int keySlot = RedisSlot.getSlot("foo");
+//    	String node2Id = getNodeId(node2.clusterNodes());
+//    	node1.clusterSetSlotMigrating(keySlot, node2Id);
+//    	node1.get("foo");
+//    }
+    
+    private String getNodeId(String infoOutput) {
+    	for (String infoLine : infoOutput.split("\n")) {
+			if (infoLine.contains("myself")) {
+				return infoLine.split(" ")[0];
+			}
+		}
+    	return "";
     }
 }
\ No newline at end of file
diff --git a/src/test/java/redis/clients/jedis/tests/utils/RedisSlot.java b/src/test/java/redis/clients/jedis/tests/utils/RedisSlot.java
new file mode 100644
index 0000000..1dd76c3
--- /dev/null
+++ b/src/test/java/redis/clients/jedis/tests/utils/RedisSlot.java
@@ -0,0 +1,25 @@
+package redis.clients.jedis.tests.utils;
+
+public class RedisSlot {
+	public final static int polynomial = 0x1021;	// Represents x^16+x^12+x^5+1
+	static int crc;
+	
+	public RedisSlot(){
+		crc = 0x0000;
+	}
+	
+	public static int getSlot(String key) { 
+        for (byte b : key.getBytes()) {
+            for (int i = 0; i < 8; i++) {
+                boolean bit = ((b   >> (7-i) & 1) == 1);
+                boolean c15 = ((crc >> 15    & 1) == 1);
+                crc <<= 1;
+                // If coefficient of bit and remainder polynomial = 1 xor crc with polynomial
+                if (c15 ^ bit) crc ^= polynomial;
+             }
+        }
+
+        return crc &= 0xffff % 16384;
+    }	
+	
+}
\ No newline at end of file