[SPARK-17332][CORE] Make Java Loggers static members

## What changes were proposed in this pull request?

Make all Java Loggers static members

## How was this patch tested?

Jenkins

Author: Sean Owen <sowen@cloudera.com>

Closes #14896 from srowen/SPARK-17332.

1 files changed, 1 insertions, 1 deletions

diff --git a/common/network-common/src/main/java/org/apache/spark/network/server/TransportChannelHandler.java b/common/network-common/src/main/java/org/apache/spark/network/server/TransportChannelHandler.java
index 884ea7d115..c33848c840 100644
--- a/common/network-common/src/main/java/org/apache/spark/network/server/TransportChannelHandler.java
+++ b/common/network-common/src/main/java/org/apache/spark/network/server/TransportChannelHandler.java
@@ -49,7 +49,7 @@ import static org.apache.spark.network.util.NettyUtils.getRemoteAddress;
  * timeout if the client is continuously sending but getting no responses, for simplicity.
  */
 public class TransportChannelHandler extends SimpleChannelInboundHandler<Message> {
-  private final Logger logger = LoggerFactory.getLogger(TransportChannelHandler.class);
+  private static final Logger logger = LoggerFactory.getLogger(TransportChannelHandler.class);
 
   private final TransportClient client;
   private final TransportResponseHandler responseHandler;