2 minor improvements from review

erans · Nov 30, 2010 · 0815fda · 0815fda
1 parent 1b9782c
commit 0815fda
Showing 1 changed file with 8 additions and 7 deletions.
diff --git a/src/main/scala/com/twitter/service/snowflake/IdWorker.scala b/src/main/scala/com/twitter/service/snowflake/IdWorker.scala
@@ -26,7 +26,7 @@ class IdWorker(workerId: Long, datacenterId: Long) extends Snowflake.Iface {
   private val datacenterIdBits = 5L
   private val maxWorkerId = -1L ^ (-1L << workerIdBits)
   private val maxDatacenterId = -1L ^ (-1L << datacenterIdBits)
-  private val sequenceBits = 12
+  private val sequenceBits = 12L
 
   private val workerIdShift = sequenceBits
   private val datacenterIdShift = sequenceBits + workerIdBits
@@ -68,12 +68,6 @@ class IdWorker(workerId: Long, datacenterId: Long) extends Snowflake.Iface {
   protected[snowflake] def nextId(): Long = synchronized {
     var timestamp = timeGen()
 
-    if (timestamp < lastTimestamp) {
-      exceptionCounter.incr(1)
-      log.error("clock is moving backwards.  Rejecting requests until %d.", lastTimestamp);
-      throw new InvalidSystemClock("Clock moved backwards.  Refusing to generate id for %d milliseconds".format(lastTimestamp - timestamp));
-    }
-
     if (lastTimestamp == timestamp) {
       sequence = (sequence + 1) & sequenceMask
       if (sequence == 0) {
@@ -83,6 +77,13 @@ class IdWorker(workerId: Long, datacenterId: Long) extends Snowflake.Iface {
       sequence = 0
     }
 
+    if (timestamp < lastTimestamp) {
+      exceptionCounter.incr(1)
+      log.error("clock is moving backwards.  Rejecting requests until %d.", lastTimestamp);
+      throw new InvalidSystemClock("Clock moved backwards.  Refusing to generate id for %d milliseconds".format(lastTimestamp - timestamp));
+    }
+
+
     lastTimestamp = timestamp
     genCounter.incr()
     ((timestamp - twepoch) << timestampLeftShift) |