Revert "HBASE-16880 Reduce garbage in BufferChain (binlijin)" to fix JIRA number

This reverts commit ce493642c0.

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/BufferChain.java

@@ -20,6 +20,8 @@ package org.apache.hadoop.hbase.ipc;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.channels.GatheringByteChannel;
+import java.util.ArrayList;
+import java.util.List;
 
 import org.apache.hadoop.hbase.classification.InterfaceAudience;
 
@@ -33,11 +35,22 @@ class BufferChain {
   private int remaining = 0;
   private int bufferOffset = 0;
 
-  BufferChain(ByteBuffer[] buffers) {
+  BufferChain(ByteBuffer ... buffers) {
+    // Some of the incoming buffers can be null
+    List<ByteBuffer> bbs = new ArrayList<ByteBuffer>(buffers.length);
+    for (ByteBuffer b : buffers) {
+      if (b == null) continue;
+      bbs.add(b);
+      this.remaining += b.remaining();
+    }
+    this.buffers = bbs.toArray(new ByteBuffer[bbs.size()]);
+  }
+
+  BufferChain(List<ByteBuffer> buffers) {
     for (ByteBuffer b : buffers) {
       this.remaining += b.remaining();
     }
-    this.buffers = buffers;
+    this.buffers = buffers.toArray(new ByteBuffer[buffers.size()]);
   }
 
   /**

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServer.java

@@ -411,9 +411,7 @@ public class RpcServer implements RpcServerInterface, ConfigurationObserver {
     }
 
     protected synchronized void setSaslTokenResponse(ByteBuffer response) {
-      ByteBuffer[] responseBufs = new ByteBuffer[1];
+      this.response = new BufferChain(response);
-      responseBufs[0] = response;
-      this.response = new BufferChain(responseBufs);
     }
 
     protected synchronized void setResponse(Object m, final CellScanner cells,
@@ -460,20 +458,10 @@ public class RpcServer implements RpcServerInterface, ConfigurationObserver {
         }
         Message header = headerBuilder.build();
         byte[] b = createHeaderAndMessageBytes(result, header, cellBlockSize);
-        ByteBuffer[] responseBufs = null;
+        List<ByteBuffer> responseBufs = new ArrayList<ByteBuffer>(
-        int cellBlockBufferSize = 0;
+            (cellBlock == null ? 1 : cellBlock.size()) + 1);
-        if (cellBlock != null) {
+        responseBufs.add(ByteBuffer.wrap(b));
-          cellBlockBufferSize = cellBlock.size();
+        if (cellBlock != null) responseBufs.addAll(cellBlock);
-          responseBufs = new ByteBuffer[1 + cellBlockBufferSize];
-        } else {
-          responseBufs = new ByteBuffer[1];
-        }
-        responseBufs[0] = ByteBuffer.wrap(b);
-        if (cellBlock != null) {
-          for (int i = 0; i < cellBlockBufferSize; i++) {
-            responseBufs[i + 1] = cellBlock.get(i);
-          }
-        }
         bc = new BufferChain(responseBufs);
         if (connection.useWrap) {
           bc = wrapWithSasl(bc);
@@ -567,10 +555,9 @@ public class RpcServer implements RpcServerInterface, ConfigurationObserver {
             + " as call response.");
       }
 
-      ByteBuffer[] responseBufs = new ByteBuffer[2];
+      ByteBuffer bbTokenLength = ByteBuffer.wrap(Bytes.toBytes(token.length));
-      responseBufs[0] = ByteBuffer.wrap(Bytes.toBytes(token.length));
+      ByteBuffer bbTokenBytes = ByteBuffer.wrap(token);
-      responseBufs[1] = ByteBuffer.wrap(token);
+      return new BufferChain(bbTokenLength, bbTokenBytes);
-      return new BufferChain(responseBufs);
     }
 
     @Override