From f4c98563b6b2dcdfb59a9288252265e59edd7540 Mon Sep 17 00:00:00 2001
From: jxiang <jxiang@unknown>
Date: Wed, 23 Oct 2013 22:18:42 +0000
Subject: [PATCH] HBASE-9821 Scanner id could collide

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1535198 13f79535-47bb-0310-9956-ffa450edef68
---
 .../java/org/apache/hadoop/hbase/client/ScannerCallable.java  | 4 +++-
 .../org/apache/hadoop/hbase/regionserver/HRegionServer.java   | 3 +--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ScannerCallable.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ScannerCallable.java
index 3f25fcb91dc..3c6b36a40df 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ScannerCallable.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ScannerCallable.java
@@ -146,6 +146,7 @@ public class ScannerCallable extends RegionServerCallable<Result[]> {
   /**
    * @see java.util.concurrent.Callable#call()
    */
+  @SuppressWarnings("deprecation")
   public Result [] call() throws IOException {
     if (closed) {
       if (scannerId != -1) {
@@ -199,7 +200,8 @@ public class ScannerCallable extends RegionServerCallable<Result[]> {
           updateResultsMetrics(rrs);
         } catch (IOException e) {
           if (logScannerActivity) {
-            LOG.info("Got exception making request " + TextFormat.shortDebugString(request), e);
+            LOG.info("Got exception making request " + TextFormat.shortDebugString(request)
+              + " to " + getLocation(), e);
           }
           IOException ioe = e;
           if (e instanceof RemoteException) {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java
index d746c79334c..8dd38276cc3 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java
@@ -2707,8 +2707,7 @@ public class HRegionServer implements ClientProtos.ClientService.BlockingInterfa
   protected long addScanner(RegionScanner s) throws LeaseStillHeldException {
     long scannerId = -1;
     while (true) {
-      scannerId = rand.nextLong();
-      if (scannerId == -1) continue;
+      scannerId = Math.abs(rand.nextLong() << 24) ^ startcode;
       String scannerName = String.valueOf(scannerId);
       RegionScannerHolder existing = scanners.putIfAbsent(scannerName, new RegionScannerHolder(s));
       if (existing == null) {