[refactor][bookkeeper] Refactor ByteBuf release method in DefaultEntr…

…yLogger (apache#3673)

(cherry picked from commit 8fce024)

bookkeeper-server/src/main/java/org/apache/bookkeeper/bookie/EntryLogger.java

@@ -32,6 +32,7 @@
 import io.netty.buffer.ByteBufAllocator;
 import io.netty.buffer.PooledByteBufAllocator;
 import io.netty.buffer.Unpooled;
+import io.netty.util.ReferenceCountUtil;
 import io.netty.util.concurrent.FastThreadLocal;
 import java.io.BufferedReader;
 import java.io.File;
@@ -188,7 +189,7 @@ public void accept(long ledgerId, long size) {
                     throw e;
                 }
             } finally {
-                serializedMap.release();
+                ReferenceCountUtil.safeRelease(serializedMap);
             }
             // Flush the ledger's map out before we write the header.
             // Otherwise the header might point to something that is not fully
@@ -836,7 +837,7 @@ public ByteBuf internalReadEntry(long ledgerId, long entryId, long location, boo
         ByteBuf data = allocator.buffer(entrySize, entrySize);
         int rc = readFromLogChannel(entryLogId, fc, data, pos);
         if (rc != entrySize) {
-            data.release();
+            ReferenceCountUtil.safeRelease(data);
             throw new IOException("Bad entry read from log file id: " + entryLogId,
                     new EntryLookupException("Short read for " + ledgerId + "@"
                                               + entryId + " in " + entryLogId + "@"
@@ -874,7 +875,7 @@ private Header getHeaderForLogId(long entryLogId) throws IOException {
             int ledgersCount = headers.readInt();
             return new Header(headerVersion, ledgersMapOffset, ledgersCount);
         } finally {
-            headers.release();
+            ReferenceCountUtil.safeRelease(headers);
         }
     }
 
@@ -1020,7 +1021,7 @@ public void scanEntryLog(long entryLogId, EntryLogScanner scanner) throws IOExce
                 pos += entrySize;
             }
         } finally {
-            data.release();
+            ReferenceCountUtil.safeRelease(data);
         }
     }
 
@@ -1109,7 +1110,7 @@ EntryLogMetadata extractEntryLogMetadataFromIndex(long entryLogId) throws IOExce
         } catch (IndexOutOfBoundsException e) {
             throw new IOException(e);
         } finally {
-            ledgersMap.release();
+            ReferenceCountUtil.safeRelease(ledgersMap);
         }
 
         if (meta.getLedgersMap().size() != header.ledgersCount) {