From 8c93bd1e582a05bd29b96aa45525895f79b65d9d Mon Sep 17 00:00:00 2001
From: Jochen Meierhofer <jochen.meierhofer@systemlogistics.de>
Date: Thu, 7 Nov 2024 17:45:50 +0100
Subject: [PATCH] fix(plc4j/drivers/s7): fix NoSuchElementException when
 watchdog ChannelHandler was not added yet & fix unnecessary warning in
 logfile/console due to exception "MessageToMessageCodec$1 must produce at
 least one message."

---
 .../java/s7/readwrite/protocol/S7HMuxImpl.java   | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/plc4j/drivers/s7/src/main/java/org/apache/plc4x/java/s7/readwrite/protocol/S7HMuxImpl.java b/plc4j/drivers/s7/src/main/java/org/apache/plc4x/java/s7/readwrite/protocol/S7HMuxImpl.java
index d58b8e32c4..d59eb17048 100644
--- a/plc4j/drivers/s7/src/main/java/org/apache/plc4x/java/s7/readwrite/protocol/S7HMuxImpl.java
+++ b/plc4j/drivers/s7/src/main/java/org/apache/plc4x/java/s7/readwrite/protocol/S7HMuxImpl.java
@@ -20,6 +20,7 @@
 
 import io.netty.buffer.ByteBuf;
 import io.netty.channel.Channel;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandler.Sharable;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.embedded.EmbeddedChannel;
@@ -130,9 +131,8 @@ protected void encode(ChannelHandlerContext ctx, ByteBuf outBB, List<Object> lis
         if ((embedCtx == null) && (ctx.channel() instanceof EmbeddedChannel)) embedCtx = ctx;
         if ((tcpChannel != null) && (embedCtx == ctx)) {
             tcpChannel.writeAndFlush(outBB.copy());
-        } else {
-            list.add(outBB.copy());
         }
+        list.add(outBB.copy());
     }
 
     /*
@@ -175,9 +175,14 @@ public void channelWritabilityChanged(ChannelHandlerContext ctx) throws Exceptio
     public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
         super.userEventTriggered(ctx, evt);
         logger.info(LocalTime.now() + " userEventTriggered: " + ctx.name() + " Event: " + evt);
+
         if (evt instanceof ConnectedEvent) {
             try {
-                tcpChannel.pipeline().remove("watchdog");
+                ChannelHandler watchdog = tcpChannel.pipeline().get("watchdog");
+                if (watchdog != null) {
+                    tcpChannel.pipeline().remove(watchdog);
+                }
+
             } catch (Exception ex) {
                 logger.info(ex.toString());
             }
@@ -199,7 +204,6 @@ public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exc
         if (evt instanceof DisconnectEvent) {
             logger.info("DisconnectEvent");
         }
-
     }
 
     @Override
@@ -250,7 +254,6 @@ public void channelUnregistered(ChannelHandlerContext ctx) throws Exception {
                         embededChannel.pipeline().fireUserEventTriggered(new ConnectEvent());
                     }
                 }
-        ;
 
 
         if ((tcpChannel == secondaryChannel) &&
@@ -265,10 +268,8 @@ public void channelUnregistered(ChannelHandlerContext ctx) throws Exception {
                         embededChannel.pipeline().fireUserEventTriggered(new ConnectEvent());
                     }
                 }
-
     }
 
-
     @Override
     public void setEmbededhannel(Channel embeded_channel, PlcConnectionConfiguration configuration) {
         final S7Configuration conf = (S7Configuration) configuration;
@@ -351,5 +352,4 @@ public Channel getTCPChannel() {
         return tcpChannel;
     }
 
-
 }