From 25607c0d8300e77cb96fe166cec066d6245d43a4 Mon Sep 17 00:00:00 2001
From: Norman Maurer <norman_maurer@apple.com>
Date: Wed, 15 Apr 2020 09:08:19 +0200
Subject: [PATCH] CodecOutputList should be recycled in a finally block
 (#10186)

Motivation:

To ensure we always recycle the CodecOutputList we should better do it in a finally block

Modifications:

Call CodecOutputList.recycle() in finally

Result:

Less chances of non-recycled lists. Related to https://github.com/netty/netty/issues/10183
---
 .../codec/MessageToMessageEncoder.java        | 28 +++++++++----------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/codec/src/main/java/io/netty/handler/codec/MessageToMessageEncoder.java b/codec/src/main/java/io/netty/handler/codec/MessageToMessageEncoder.java
index bfad9eb32d..e2ea123a20 100644
--- a/codec/src/main/java/io/netty/handler/codec/MessageToMessageEncoder.java
+++ b/codec/src/main/java/io/netty/handler/codec/MessageToMessageEncoder.java
@@ -92,9 +92,6 @@ public abstract class MessageToMessageEncoder<I> extends ChannelHandlerAdapter {
                 }
 
                 if (out.isEmpty()) {
-                    out.recycle();
-                    out = null;
-
                     throw new EncoderException(
                             StringUtil.simpleClassName(this) + " must produce at least one message.");
                 }
@@ -107,19 +104,22 @@ public abstract class MessageToMessageEncoder<I> extends ChannelHandlerAdapter {
             throw new EncoderException(t);
         } finally {
             if (out != null) {
-                final int sizeMinusOne = out.size() - 1;
-                if (sizeMinusOne == 0) {
-                    ctx.write(out.getUnsafe(0), promise);
-                } else if (sizeMinusOne > 0) {
-                    // Check if we can use a voidPromise for our extra writes to reduce GC-Pressure
-                    // See https://github.com/netty/netty/issues/2525
-                    if (promise == ctx.voidPromise()) {
-                        writeVoidPromise(ctx, out);
-                    } else {
-                        writePromiseCombiner(ctx, out, promise);
+                try {
+                    final int sizeMinusOne = out.size() - 1;
+                    if (sizeMinusOne == 0) {
+                        ctx.write(out.getUnsafe(0), promise);
+                    } else if (sizeMinusOne > 0) {
+                        // Check if we can use a voidPromise for our extra writes to reduce GC-Pressure
+                        // See https://github.com/netty/netty/issues/2525
+                        if (promise == ctx.voidPromise()) {
+                            writeVoidPromise(ctx, out);
+                        } else {
+                            writePromiseCombiner(ctx, out, promise);
+                        }
                     }
+                } finally {
+                    out.recycle();
                 }
-                out.recycle();
             }
         }
     }