From fb154e3a032d99ad535cbb749fe3ee126347e102 Mon Sep 17 00:00:00 2001
From: Hairong Kuang <hairong@apache.org>
Date: Thu, 8 Apr 2010 21:13:58 +0000
Subject: [PATCH] HADOOP-6691. TestFileSystemCaching sometimes hangs.
 Contributed by Hairong Kuang.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@932115 13f79535-47bb-0310-9956-ffa450edef68
---
 CHANGES.txt                                        |  2 ++
 .../apache/hadoop/fs/TestFileSystemCaching.java    | 14 ++++++--------
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/CHANGES.txt b/CHANGES.txt
index 8df0dbcaa6..26c95ae7e5 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -312,6 +312,8 @@ Trunk (unreleased changes)
     HADOOP-6680. hadoop-cloud push command invokes proxy creation.
     (Andrew Klochkov via tomwhite)
 
+    HADOOP-6691. TestFileSystemCaching sometimes hangs. (hairong)
+
 Release 0.21.0 - Unreleased
 
   INCOMPATIBLE CHANGES
diff --git a/src/test/core/org/apache/hadoop/fs/TestFileSystemCaching.java b/src/test/core/org/apache/hadoop/fs/TestFileSystemCaching.java
index 1fb66f583a..b860282fa3 100644
--- a/src/test/core/org/apache/hadoop/fs/TestFileSystemCaching.java
+++ b/src/test/core/org/apache/hadoop/fs/TestFileSystemCaching.java
@@ -30,9 +30,9 @@
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.security.token.TokenIdentifier;
 import org.junit.Test;
-import java.security.PrivilegedAction;
-import java.security.PrivilegedActionException;
 import java.security.PrivilegedExceptionAction;
+import java.util.concurrent.Semaphore;
+
 import static org.mockito.Mockito.mock;
 
 
@@ -49,11 +49,10 @@ public void testCacheEnabled() throws Exception {
   }
 
   public static class InitializeForeverFileSystem extends LocalFileSystem {
+    final static Semaphore sem = new Semaphore(0);
     public void initialize(URI uri, Configuration conf) throws IOException {
       // notify that InitializeForeverFileSystem started initialization
-      synchronized (conf) {
-        conf.notify();
-      }
+      sem.release();
       try {
         while (true) {
           Thread.sleep(1000);
@@ -82,9 +81,8 @@ public void run() {
     };
     t.start();
     // wait for InitializeForeverFileSystem to start initialization
-    synchronized (conf) {
-      conf.wait();
-    }
+    InitializeForeverFileSystem.sem.acquire();
+    
     conf.set("fs.cachedfile.impl", conf.get("fs.file.impl"));
     FileSystem.get(new URI("cachedfile://a"), conf);
     t.interrupt();