[GitHub] [bookkeeper] nicoloboschi commented on a change in pull request #2742: Abstract the FileChannel in the JournalChannel

[GitBox <gi...@apache.org>]

nicoloboschi commented on a change in pull request #2742:
URL: https://github.com/apache/bookkeeper/pull/2742#discussion_r697395142



##########
File path: bookkeeper-server/src/main/java/org/apache/bookkeeper/conf/ServerConfiguration.java
##########
@@ -868,6 +869,15 @@ public long getJournalPageCacheFlushIntervalMSec() {
         return this.getLong(JOURNAL_PAGECACHE_FLUSH_INTERVAL_MSEC, 1000);
     }
 
+    public ServerConfiguration setJournalChannelProvider(String journalChannelProvider) {

Review comment:
       javadoc for setter and getter ? 

##########
File path: bookkeeper-server/src/main/java/org/apache/bookkeeper/bookie/JournalChannel.java
##########
@@ -180,8 +191,7 @@ private JournalChannel(File journalDirectory, long logId,
             nextPrealloc = this.preAllocSize;
             fc.write(zeros, nextPrealloc - journalAlignSize);
         } else {  // open an existing file
-            randomAccessFile = new RandomAccessFile(fn, "r");
-            fc = openFileChannel(randomAccessFile);

Review comment:
       openFileChannel method could be removed now ? 

##########
File path: bookkeeper-server/src/main/java/org/apache/bookkeeper/conf/ServerConfiguration.java
##########
@@ -868,6 +869,15 @@ public long getJournalPageCacheFlushIntervalMSec() {
         return this.getLong(JOURNAL_PAGECACHE_FLUSH_INTERVAL_MSEC, 1000);
     }
 
+    public ServerConfiguration setJournalChannelProvider(String journalChannelProvider) {

Review comment:
       I feel it would be good to say that the class must implements FileChannelProvider and an no args constructor is needed

##########
File path: bookkeeper-server/src/main/java/org/apache/bookkeeper/bookie/DefaultFileChannel.java
##########
@@ -0,0 +1,75 @@
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+
+package org.apache.bookkeeper.bookie;
+
+import java.io.File;
+import java.io.FileDescriptor;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.nio.channels.FileChannel;
+import org.apache.bookkeeper.conf.ServerConfiguration;
+
+class DefaultFileChannel implements BookieFileChannel {
+    private final File file;
+    private RandomAccessFile randomAccessFile;
+    private final ServerConfiguration configuration;
+
+    DefaultFileChannel(File file, ServerConfiguration serverConfiguration) throws IOException {
+        this.file = file;
+        this.configuration = serverConfiguration;
+    }
+
+    @Override
+    public FileChannel getFileChannel() throws FileNotFoundException {
+        synchronized (this) {
+            if (randomAccessFile == null) {
+                randomAccessFile = new RandomAccessFile(file, "rw");
+            }
+            return randomAccessFile.getChannel();
+        }
+    }
+
+    @Override
+    public boolean fileExists(File file) {
+        return file.exists();
+    }
+
+    @Override
+    public FileDescriptor getFD() throws IOException {
+        synchronized (this) {
+            if (randomAccessFile == null) {
+                throw new IOException("randomAccessFile is null, please initialize it by calling getFileChannel");
+            }
+            return randomAccessFile.getFD();
+        }
+    }
+
+    @Override
+    public void close() throws IOException {
+        synchronized (this) {

Review comment:
       It looks like the close() method of RandomAccessFile wasn't called before
   and fd and channel related to the file were closed due to `BufferedChannel#close()` method
   
   However closing the RandomAccessFile twice is not a problem, so we can keep it as is




-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: issues-unsubscribe@bookkeeper.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org