[kudu] branch master updated: [java] fix bug in getClosestServerInfo code

[zhangyifan]

This is an automated email from the ASF dual-hosted git repository.

zhangyifan pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/kudu.git


The following commit(s) were added to refs/heads/master by this push:
     new acabee5  [java] fix bug in getClosestServerInfo code
acabee5 is described below

commit acabee5514573475aa944492dd763b219a3f0d60
Author: zhangyifan27 <chinazhangyi...@163.com>
AuthorDate: Mon Mar 16 13:35:59 2020 +0800

    [java] fix bug in getClosestServerInfo code
    
    When client handles tablet not found error, it removes the tablet server
    from the RemoteTablet's locations. If all tablet servers are removed,
    the code in getClosestServerInfo will throw a division by zero exception.
    This patch fixed it and added a test to verify getClosestServerInfo
    returns null when all locations of a tablet are invalid.
    
    Change-Id: Ib4dc471b5044ea4b5bd6202ccd2a707d6e229ea0
    Reviewed-on: http://gerrit.cloudera.org:8080/15444
    Reviewed-by: Adar Dembo <a...@cloudera.com>
    Tested-by: Kudu Jenkins
---
 .../src/main/java/org/apache/kudu/client/RemoteTablet.java  |  3 +++
 .../test/java/org/apache/kudu/client/TestRemoteTablet.java  | 13 +++++++++++++
 2 files changed, 16 insertions(+)

diff --git 
a/java/kudu-client/src/main/java/org/apache/kudu/client/RemoteTablet.java 
b/java/kudu-client/src/main/java/org/apache/kudu/client/RemoteTablet.java
index 5ed424f..e330a6e 100644
--- a/java/kudu-client/src/main/java/org/apache/kudu/client/RemoteTablet.java
+++ b/java/kudu-client/src/main/java/org/apache/kudu/client/RemoteTablet.java
@@ -196,6 +196,9 @@ public class RemoteTablet implements 
Comparable<RemoteTablet> {
     // TODO(wdberkeley): Eventually, the client might use the hierarchical
     // structure of a location to determine proximity.
     synchronized (tabletServers) {
+      if (tabletServers.isEmpty()) {
+        return null;
+      }
       ServerInfo result = null;
       List<ServerInfo> localServers = new ArrayList<>();
       List<ServerInfo> serversInSameLocation = new ArrayList<>();
diff --git 
a/java/kudu-client/src/test/java/org/apache/kudu/client/TestRemoteTablet.java 
b/java/kudu-client/src/test/java/org/apache/kudu/client/TestRemoteTablet.java
index 44d652a..f793e41 100644
--- 
a/java/kudu-client/src/test/java/org/apache/kudu/client/TestRemoteTablet.java
+++ 
b/java/kudu-client/src/test/java/org/apache/kudu/client/TestRemoteTablet.java
@@ -147,6 +147,19 @@ public class TestRemoteTablet {
   }
 
   @Test
+  public void testReplicaWithNoValidLocation() {
+    RemoteTablet tablet = getTablet(0, 1, 2);
+
+    // Test removing all tablet servers doesn't break.
+    for (String uuid : kUuids) {
+      assertTrue(tablet.removeTabletClient(uuid));
+    }
+    assertNull(tablet.getLeaderServerInfo());
+    assertNull(tablet.getClosestServerInfo(kNoLocation));
+    assertNull(tablet.getClosestServerInfo(kClientLocation));
+  }
+
+  @Test
   public void testReplicaSelection() {
     {
       RemoteTablet tablet = getTablet(0, 1, 2);