HADOOP-7963. Fix ViewFS to catch a null canonical service-name and pass tests TestViewFileSystem* (Siddharth Seth via vinodkv)

svn merge --ignore-ancestry -c 1229379 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1229382 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -123,6 +123,9 @@ Release 0.23.1 - Unreleased
 
    HADOOP-7936. There's a Hoop README in the root dir of the tarball. (tucu)
 
+   HADOOP-7963. Fix ViewFS to catch a null canonical service-name and pass
+   tests TestViewFileSystem* (Siddharth Seth via vinodkv)
+
 Release 0.23.0 - 2011-11-01 
 
   INCOMPATIBLE CHANGES

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/viewfs/ViewFileSystem.java

@@ -514,7 +514,7 @@ public class ViewFileSystem extends FileSystem {
     for (int i = 0; i < mountPoints.size(); ++i) {
       String serviceName =
           mountPoints.get(i).target.targetFileSystem.getCanonicalServiceName();
-      if (seenServiceNames.contains(serviceName)) {
+      if (serviceName == null || seenServiceNames.contains(serviceName)) {
         continue;
       }
       seenServiceNames.add(serviceName);