From a2732c6542d24cb28ee32f612f7c97c9d2216a54 Mon Sep 17 00:00:00 2001
From: Norman Maurer <norman_maurer@apple.com>
Date: Tue, 26 Jan 2016 15:03:59 +0100
Subject: [PATCH] [#4755] Make WebSocketClientCompressionHandler @Sharable

Motivation:

WebSocketClientCompressionHandler is stateless so it should be @Sharable.

Modifications:

Add @Sharable annotation to WebSocketClientCompressionHandler, make constructor private and add static field to get the instance.

Result:

Less object creation.
---
 .../WebSocketClientCompressionHandler.java            | 11 ++++++-----
 .../http/websocketx/client/WebSocketClient.java       |  2 +-
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/codec-http/src/main/java/io/netty/handler/codec/http/websocketx/extensions/compression/WebSocketClientCompressionHandler.java b/codec-http/src/main/java/io/netty/handler/codec/http/websocketx/extensions/compression/WebSocketClientCompressionHandler.java
index 3596ab658f..bfd0375acc 100644
--- a/codec-http/src/main/java/io/netty/handler/codec/http/websocketx/extensions/compression/WebSocketClientCompressionHandler.java
+++ b/codec-http/src/main/java/io/netty/handler/codec/http/websocketx/extensions/compression/WebSocketClientCompressionHandler.java
@@ -15,6 +15,7 @@
  */
 package io.netty.handler.codec.http.websocketx.extensions.compression;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.handler.codec.http.websocketx.extensions.WebSocketClientExtensionHandler;
 
 /**
@@ -23,12 +24,12 @@ import io.netty.handler.codec.http.websocketx.extensions.WebSocketClientExtensio
  *
  * See <tt>io.netty.example.http.websocketx.client.WebSocketClient</tt> for usage.
  */
-public class WebSocketClientCompressionHandler extends WebSocketClientExtensionHandler {
+@ChannelHandler.Sharable
+public final class WebSocketClientCompressionHandler extends WebSocketClientExtensionHandler {
 
-    /**
-     * Constructor with default configuration.
-     */
-    public WebSocketClientCompressionHandler() {
+    public static final WebSocketClientCompressionHandler INSTANCE = new WebSocketClientCompressionHandler();
+
+    private WebSocketClientCompressionHandler() {
         super(new PerMessageDeflateClientExtensionHandshaker(),
                 new DeflateFrameClientExtensionHandshaker(false),
                 new DeflateFrameClientExtensionHandshaker(true));
diff --git a/example/src/main/java/io/netty/example/http/websocketx/client/WebSocketClient.java b/example/src/main/java/io/netty/example/http/websocketx/client/WebSocketClient.java
index 4c56d6c3ae..8aa3b5cdbc 100644
--- a/example/src/main/java/io/netty/example/http/websocketx/client/WebSocketClient.java
+++ b/example/src/main/java/io/netty/example/http/websocketx/client/WebSocketClient.java
@@ -113,7 +113,7 @@ public final class WebSocketClient {
                      p.addLast(
                              new HttpClientCodec(),
                              new HttpObjectAggregator(8192),
-                             new WebSocketClientCompressionHandler(),
+                             WebSocketClientCompressionHandler.INSTANCE,
                              handler);
                  }
              });