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https://issues.apache.org/jira/browse/CURATOR-171?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15821815#comment-15821815
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Tsuyoshi Ozawa commented on CURATOR-171:
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[~vines] [~psgrewa...@gmail.com] Thanks for reporting this issue. After talking 
with Jordan on https://github.com/apache/curator/pull/195, I noticed that the 
latch code handles connection loss / reconnection correctly: after detecting 
the changes, the leader mark itself as "not a leader". As reported, the test 
case described is not handled, but it cannot happen when using leader latch. Am 
I missing something? Please correct me if I'm wrong. Thanks :-)

> LeaderLatch isn't aware if it's own ephemeral node goes away
> ------------------------------------------------------------
>
>                 Key: CURATOR-171
>                 URL: https://issues.apache.org/jira/browse/CURATOR-171
>             Project: Apache Curator
>          Issue Type: Bug
>          Components: Recipes
>            Reporter: John Vines
>
> Running the following code- {code}  public static void main(String args[]) 
> throws Exception {
>     CuratorFramework curator = 
> CuratorFrameworkFactory.builder().connectString("localhost:2181").retryPolicy(new
>  ExponentialBackoffRetry(1000, 5))
>         .authorization("digest", "accumulo:DEFAULT".getBytes()).build();
>     curator.start();
>     LeaderLatch latch = new LeaderLatch(curator, "/latch", "test");
>     LeaderLatch latch2 = new LeaderLatch(curator, "/latch", "test2");
>     latch.addListener(new LeaderLatchListener() {
>       @Override
>       public void isLeader() {
>         System.out.println("Became leader!");
>       }
>       @Override
>       public void notLeader() {
>         System.out.println("Lost leadership!");
>       }
>     });
>     latch.start();
>     latch.await();
>     latch2.start();
>     Thread.sleep(1000);
>     System.out.println("Does latch1 have leadership? " + 
> latch.hasLeadership());
>     System.out.println("Does latch2 have leadership? " + 
> latch2.hasLeadership());
>     for (String child : curator.getChildren().forPath("/latch"))
>       if (Arrays.equals(curator.getData().forPath(ZKPaths.makePath("/latch", 
> child)), "test".getBytes()))
>           
> curator.delete().deletingChildrenIfNeeded().forPath(ZKPaths.makePath("/latch",
>  child));
>     Thread.sleep(1000);
>     System.out.println("Does latch1 have leadership? " + 
> latch.hasLeadership());
>     System.out.println("Does latch2 have leadership? " + 
> latch2.hasLeadership());
>     
>     Thread.sleep(1000 * 40);
>     System.out.println("Does latch1 have leadership? " + 
> latch.hasLeadership());
>     System.out.println("Does latch2 have leadership? " + 
> latch2.hasLeadership());
>     
>     latch.close();
>     latch2.close();
>     curator.close();
>   }{code}
> I get the following output-{noformat}Became leader!
> Does latch1 have leadership? true
> Does latch2 have leadership? false
> Does latch1 have leadership? true
> Does latch2 have leadership? true
> Does latch1 have leadership? true
> Does latch2 have leadership? true
> {noformat}
> I expect that when the ephemeral node is deleted, latch1 no longer reports 
> itself as having leadership. Furthermore, I expect it to trigger the 
> notLeader call.



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