From 5e36f65e0e29456c422c90854e1babef8a679980 Mon Sep 17 00:00:00 2001
From: gtully <gary.tully@gmail.com>
Date: Fri, 15 May 2015 13:23:12 +0100
Subject: [PATCH] https://issues.apache.org/jira/browse/AMQ-4705 - lastmod
 granualarity is second on some nix. Also write on lock acquire to ensure
 modification time change

---
 .../org/apache/activemq/util/LockFile.java     | 18 +++++++++---------
 .../store/kahadb/KahaDBDeleteLockTest.java     | 15 +++++++++++++--
 2 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/activemq-broker/src/main/java/org/apache/activemq/util/LockFile.java b/activemq-broker/src/main/java/org/apache/activemq/util/LockFile.java
index 45e26caaa1..516c5c25dc 100644
--- a/activemq-broker/src/main/java/org/apache/activemq/util/LockFile.java
+++ b/activemq-broker/src/main/java/org/apache/activemq/util/LockFile.java
@@ -24,7 +24,6 @@ import java.io.IOException;
 import java.io.RandomAccessFile;
 import java.nio.channels.FileLock;
 import java.nio.channels.OverlappingFileLockException;
-import java.util.Calendar;
 import java.util.Date;
 
 /**
@@ -39,7 +38,7 @@ public class LockFile {
     private long lastModified;
 
     private FileLock lock;
-    private RandomAccessFile readFile;
+    private RandomAccessFile randomAccessLockFile;
     private int lockCounter;
     private final boolean deleteOnUnlock;
     private volatile boolean locked;
@@ -72,18 +71,19 @@ public class LockFile {
         }
         try {
             if (lock == null) {
-                readFile = new RandomAccessFile(file, "rw");
+                randomAccessLockFile = new RandomAccessFile(file, "rw");
                 IOException reason = null;
                 try {
-                    lock = readFile.getChannel().tryLock(0, Math.max(1, readFile.getChannel().size()), false);
+                    lock = randomAccessLockFile.getChannel().tryLock(0, Math.max(1, randomAccessLockFile.getChannel().size()), false);
                 } catch (OverlappingFileLockException e) {
                     reason = IOExceptionSupport.create("File '" + file + "' could not be locked.", e);
                 } catch (IOException ioe) {
                     reason = ioe;
                 }
                 if (lock != null) {
-                    //Set lastModified only if we are able to successfully obtain the lock.
-                    readFile.getChannel().force(true);
+                    //track lastModified only if we are able to successfully obtain the lock.
+                    randomAccessLockFile.writeLong(System.currentTimeMillis());
+                    randomAccessLockFile.getChannel().force(true);
                     lastModified = file.lastModified();
                     lockCounter++;
                     System.setProperty(getVmLockKey(), new Date().toString());
@@ -141,12 +141,12 @@ public class LockFile {
 
     private void closeReadFile() {
         // close the file.
-        if (readFile != null) {
+        if (randomAccessLockFile != null) {
             try {
-                readFile.close();
+                randomAccessLockFile.close();
             } catch (Throwable ignore) {
             }
-            readFile = null;
+            randomAccessLockFile = null;
         }
     }
 
diff --git a/activemq-unit-tests/src/test/java/org/apache/activemq/store/kahadb/KahaDBDeleteLockTest.java b/activemq-unit-tests/src/test/java/org/apache/activemq/store/kahadb/KahaDBDeleteLockTest.java
index 53de60335b..390072e95d 100644
--- a/activemq-unit-tests/src/test/java/org/apache/activemq/store/kahadb/KahaDBDeleteLockTest.java
+++ b/activemq-unit-tests/src/test/java/org/apache/activemq/store/kahadb/KahaDBDeleteLockTest.java
@@ -21,15 +21,19 @@ import org.apache.activemq.util.Wait;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.File;
 import java.io.RandomAccessFile;
+import java.util.Date;
 import java.util.concurrent.TimeUnit;
 
 
 import static org.junit.Assert.assertTrue;
 
 public class KahaDBDeleteLockTest {
+    static final Logger LOG = LoggerFactory.getLogger(KahaDBDeleteLockTest.class);
 
     protected BrokerService master;
 
@@ -48,6 +52,12 @@ public class KahaDBDeleteLockTest {
         masterPersistenceAdapter.setDirectory(kahaDataDir);
         masterPersistenceAdapter.setLockKeepAlivePeriod(500);
 
+        // ensure broker creates the file
+        File lockFile = new File(kahaDataDir, "lock");
+        if (lockFile.exists()) {
+            lockFile.delete();
+        }
+
         master.setPersistenceAdapter(masterPersistenceAdapter);
         master.start();
         master.waitUntilStarted();
@@ -97,12 +107,13 @@ public class KahaDBDeleteLockTest {
         assertTrue("lock file exists via modification time", Wait.waitFor(new Wait.Condition() {
             @Override
             public boolean isSatisified() throws Exception {
+                LOG.info("Lock file " + lockFile.getAbsolutePath() + ", last mod at: " + new Date(lockFile.lastModified()));
                 return lockFile.lastModified() > 0;
             }
         }));
 
-        // ensure modification will be seen, milisecond granularity
-        TimeUnit.MILLISECONDS.sleep(10);
+        // ensure modification will be seen, second granularity on some nix
+        TimeUnit.SECONDS.sleep(2);
         RandomAccessFile file = new RandomAccessFile(lockFile, "rw");
         file.write(4);
         file.getChannel().force(true);