Cleanup usage of Channel*Handler (#9959)

Motivation:

In next major version of netty users should use ChannelHandler everywhere. We should ensure we do the same

Modifications:

Replace usage of deprecated classes / interfaces with ChannelHandler

Result:

Use non-deprecated code

codec-http/src/main/java/io/netty/handler/codec/http/HttpServerExpectContinueHandler.java

@@ -17,8 +17,8 @@ package io.netty.handler.codec.http;
 
 import io.netty.buffer.Unpooled;
 import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.util.ReferenceCountUtil;
 
 import static io.netty.handler.codec.http.HttpHeaderNames.CONTENT_LENGTH;
@@ -44,7 +44,7 @@ import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1;
  *  </pre>
  * </blockquote>
  */
-public class HttpServerExpectContinueHandler implements ChannelInboundHandler {
+public class HttpServerExpectContinueHandler implements ChannelHandler {
 
     private static final FullHttpResponse EXPECTATION_FAILED = new DefaultFullHttpResponse(
             HTTP_1_1, HttpResponseStatus.EXPECTATION_FAILED, Unpooled.EMPTY_BUFFER);

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/Utf8FrameValidator.java

@@ -18,14 +18,14 @@ package io.netty.handler.codec.http.websocketx;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.handler.codec.CorruptedFrameException;
 
 /**
  *
  */
-public class Utf8FrameValidator implements ChannelInboundHandler {
+public class Utf8FrameValidator implements ChannelHandler {
 
     private int fragmentedFramesCount;
     private Utf8Validator utf8Validator;

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketClientProtocolHandler.java

@@ -16,7 +16,7 @@
 package io.netty.handler.codec.http.websocketx;
 
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelPipeline;
 import io.netty.handler.codec.http.HttpHeaders;
 
@@ -36,7 +36,7 @@ import static io.netty.handler.codec.http.websocketx.WebSocketClientProtocolConf
  * This implementation will establish the websocket connection once the connection to the remote server was complete.
  *
  * To know once a handshake was done you can intercept the
- * {@link ChannelInboundHandler#userEventTriggered(ChannelHandlerContext, Object)} and check if the event was of type
+ * {@link ChannelHandler#userEventTriggered(ChannelHandlerContext, Object)} and check if the event was of type
  * {@link ClientHandshakeStateEvent#HANDSHAKE_ISSUED} or {@link ClientHandshakeStateEvent#HANDSHAKE_COMPLETE}.
  */
 public class WebSocketClientProtocolHandler extends WebSocketProtocolHandler {

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketClientProtocolHandshakeHandler.java

@@ -17,8 +17,8 @@ package io.netty.handler.codec.http.websocketx;
 
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelPromise;
 import io.netty.handler.codec.http.FullHttpResponse;
 import io.netty.handler.codec.http.websocketx.WebSocketClientProtocolHandler.ClientHandshakeStateEvent;
@@ -29,7 +29,7 @@ import java.util.concurrent.TimeUnit;
 
 import static io.netty.util.internal.ObjectUtil.*;
 
-class WebSocketClientProtocolHandshakeHandler implements ChannelInboundHandler {
+class WebSocketClientProtocolHandshakeHandler implements ChannelHandler {
 
     private static final long DEFAULT_HANDSHAKE_TIMEOUT_MS = 10000L;
 

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketCloseFrameHandler.java

@@ -17,8 +17,8 @@ package io.netty.handler.codec.http.websocketx;
 
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelOutboundHandlerAdapter;
 import io.netty.channel.ChannelPromise;
 import io.netty.util.ReferenceCountUtil;
 import io.netty.util.concurrent.ScheduledFuture;
@@ -30,7 +30,7 @@ import java.util.concurrent.TimeUnit;
 /**
  * Send {@link CloseWebSocketFrame} message on channel close, if close frame was not sent before.
  */
-final class WebSocketCloseFrameHandler extends ChannelOutboundHandlerAdapter {
+final class WebSocketCloseFrameHandler implements ChannelHandler {
     private final WebSocketCloseStatus closeStatus;
     private final long forceCloseTimeoutMillis;
     private ChannelPromise closeSent;
@@ -70,7 +70,7 @@ final class WebSocketCloseFrameHandler extends ChannelOutboundHandlerAdapter {
             promise = promise.unvoid();
             closeSent = promise;
         }
-        super.write(ctx, msg, promise);
+        ctx.write(msg, promise);
     }
 
     private void applyCloseSentTimeout(ChannelHandlerContext ctx) {

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketFrameDecoder.java

@@ -15,7 +15,7 @@
  */
 package io.netty.handler.codec.http.websocketx;
 
-import io.netty.channel.ChannelInboundHandler;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelPipeline;
 
 /**
@@ -23,5 +23,5 @@ import io.netty.channel.ChannelPipeline;
  *
  * This makes it easier to access the added encoder later in the {@link ChannelPipeline}.
  */
-public interface WebSocketFrameDecoder extends ChannelInboundHandler {
+public interface WebSocketFrameDecoder extends ChannelHandler {
 }

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketServerProtocolHandler.java

@@ -20,7 +20,6 @@ import io.netty.channel.Channel;
 import io.netty.channel.ChannelFutureListener;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelPipeline;
 import io.netty.handler.codec.http.DefaultFullHttpResponse;
 import io.netty.handler.codec.http.FullHttpRequest;
@@ -47,7 +46,7 @@ import static io.netty.handler.codec.http.websocketx.WebSocketServerProtocolConf
  * to the <tt>io.netty.example.http.websocketx.server.WebSocketServer</tt> example.
  *
  * To know once a handshake was done you can intercept the
- * {@link ChannelInboundHandler#userEventTriggered(ChannelHandlerContext, Object)} and check if the event was instance
+ * {@link ChannelHandler#userEventTriggered(ChannelHandlerContext, Object)} and check if the event was instance
  * of {@link HandshakeComplete}, the event will contain extra information about the handshake such as the request and
  * selected subprotocol.
  */

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketServerProtocolHandshakeHandler.java

@@ -17,8 +17,8 @@ package io.netty.handler.codec.http.websocketx;
 
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.ChannelPromise;
 import io.netty.handler.codec.http.DefaultFullHttpResponse;
@@ -42,7 +42,7 @@ import static io.netty.handler.codec.http.HttpVersion.*;
 /**
  * Handles the HTTP handshake (the HTTP Upgrade request) for {@link WebSocketServerProtocolHandler}.
  */
-class WebSocketServerProtocolHandshakeHandler implements ChannelInboundHandler {
+class WebSocketServerProtocolHandshakeHandler implements ChannelHandler {
 
     private final WebSocketServerProtocolConfig serverConfig;
     private ChannelHandlerContext ctx;

codec-http/src/test/java/io/netty/handler/codec/http/HttpClientUpgradeHandlerTest.java

@@ -15,8 +15,8 @@
  */
 package io.netty.handler.codec.http;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.embedded.EmbeddedChannel;
 
 import java.util.Collection;
@@ -58,7 +58,7 @@ public class HttpClientUpgradeHandlerTest {
         }
     }
 
-    private static final class UserEventCatcher implements ChannelInboundHandler {
+    private static final class UserEventCatcher implements ChannelHandler {
         private Object evt;
 
         public Object getUserEvent() {

codec-http/src/test/java/io/netty/handler/codec/http/websocketx/WebSocketServerProtocolHandlerTest.java

@@ -18,7 +18,6 @@ package io.netty.handler.codec.http.websocketx;
 import io.netty.buffer.ByteBuf;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelPromise;
 import io.netty.channel.embedded.EmbeddedChannel;
 import io.netty.handler.codec.http.DefaultFullHttpRequest;
@@ -391,7 +390,7 @@ public class WebSocketServerProtocolHandlerTest {
         }
     }
 
-    private static class CustomTextFrameHandler implements ChannelInboundHandler {
+    private static class CustomTextFrameHandler implements ChannelHandler {
         private String content;
 
         @Override

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2FrameCodec.java

@@ -17,8 +17,8 @@ package io.netty.handler.codec.http2;
 
 import io.netty.buffer.ByteBuf;
 import io.netty.channel.Channel;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelPromise;
 import io.netty.handler.codec.UnsupportedMessageTypeException;
 import io.netty.handler.codec.http.HttpServerUpgradeHandler.UpgradeEvent;
@@ -126,7 +126,7 @@ import static io.netty.handler.codec.http2.Http2Error.NO_ERROR;
  *
  * <h3>Error Handling</h3>
  *
- * Exceptions and errors are propagated via {@link ChannelInboundHandler#exceptionCaught}. Exceptions that apply to
+ * Exceptions and errors are propagated via {@link ChannelHandler#exceptionCaught}. Exceptions that apply to
  * a specific HTTP/2 stream are wrapped in a {@link Http2FrameStreamException} and have the corresponding
  * {@link Http2FrameStream} object attached.
  *

codec-http2/src/main/java/io/netty/handler/codec/http2/InboundHttpToHttp2Adapter.java

@@ -15,8 +15,8 @@
  */
 package io.netty.handler.codec.http2;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.handler.codec.http.FullHttpMessage;
 import io.netty.handler.codec.http.HttpHeaders;
 import io.netty.handler.codec.http.HttpScheme;
@@ -26,7 +26,7 @@ import io.netty.util.internal.UnstableApi;
  * Translates HTTP/1.x object reads into HTTP/2 frames.
  */
 @UnstableApi
-public class InboundHttpToHttp2Adapter implements ChannelInboundHandler {
+public class InboundHttpToHttp2Adapter implements ChannelHandler {
     private final Http2Connection connection;
     private final Http2FrameListener listener;
 

codec-http2/src/test/java/io/netty/handler/codec/http2/Http2ConnectionRoundtripTest.java

@@ -24,7 +24,6 @@ import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
 import io.netty.channel.ChannelHandler;
-import io.netty.channel.ChannelHandlerAdapter;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelPipeline;
@@ -520,7 +519,7 @@ public class Http2ConnectionRoundtripTest {
         assertTrue(requestLatch.await(DEFAULT_AWAIT_TIMEOUT_SECONDS, SECONDS));
 
         // Add a handler that will immediately throw an exception.
-        clientChannel.pipeline().addFirst(new ChannelHandlerAdapter() {
+        clientChannel.pipeline().addFirst(new ChannelHandler() {
             @Override
             public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
                 throw Http2Exception.connectionError(PROTOCOL_ERROR, "Fake Exception");
@@ -702,7 +701,7 @@ public class Http2ConnectionRoundtripTest {
         assertTrue(requestLatch.await(DEFAULT_AWAIT_TIMEOUT_SECONDS, SECONDS));
 
         // Add a handler that will immediately throw an exception.
-        clientChannel.pipeline().addFirst(new ChannelHandlerAdapter() {
+        clientChannel.pipeline().addFirst(new ChannelHandler() {
             @Override
             public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
                 throw new RuntimeException("Fake Exception");

codec-http2/src/test/java/io/netty/handler/codec/http2/Http2MultiplexTest.java

@@ -21,7 +21,6 @@ import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandlerAdapter;
 import io.netty.channel.ChannelPromise;
 import io.netty.channel.WriteBufferWaterMark;
 import io.netty.channel.embedded.EmbeddedChannel;
@@ -137,7 +136,7 @@ public abstract class Http2MultiplexTest<C extends Http2FrameCodec> {
 
     @Test
     public void writeUnknownFrame() {
-        Http2StreamChannel childChannel = newOutboundStream(new ChannelInboundHandlerAdapter() {
+        Http2StreamChannel childChannel = newOutboundStream(new ChannelHandler() {
             @Override
             public void channelActive(ChannelHandlerContext ctx) {
                 ctx.writeAndFlush(new DefaultHttp2HeadersFrame(new DefaultHttp2Headers()));
@@ -185,7 +184,7 @@ public abstract class Http2MultiplexTest<C extends Http2FrameCodec> {
         // header frame and unknown frame
         verifyFramesMultiplexedToCorrectChannel(channel, handler, 2);
 
-        Channel childChannel = newOutboundStream(new ChannelInboundHandlerAdapter());
+        Channel childChannel = newOutboundStream(new ChannelHandler() { });
         assertTrue(childChannel.isActive());
     }
 
@@ -299,10 +298,10 @@ public abstract class Http2MultiplexTest<C extends Http2FrameCodec> {
         assertNotNull(headersFrame);
 
         childChannel.config().setAutoRead(false);
-        childChannel.pipeline().addFirst(new ChannelInboundHandlerAdapter() {
+        childChannel.pipeline().addFirst(new ChannelHandler() {
             private int count;
             @Override
-            public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
+            public void channelRead(ChannelHandlerContext ctx, Object msg) {
                 ctx.fireChannelRead(msg);
                 // Close channel after 2 reads so there is still something in the inboundBuffer when the close happens.
                 if (++count == 2) {
@@ -702,7 +701,7 @@ public abstract class Http2MultiplexTest<C extends Http2FrameCodec> {
 
     @Test
     public void writabilityOfParentIsRespected() {
-        Http2StreamChannel childChannel = newOutboundStream(new ChannelInboundHandlerAdapter());
+        Http2StreamChannel childChannel = newOutboundStream(new ChannelHandler() { });
         childChannel.config().setWriteBufferWaterMark(new WriteBufferWaterMark(2048, 4096));
         parentChannel.config().setWriteBufferWaterMark(new WriteBufferWaterMark(256, 512));
         assertTrue(childChannel.isWritable());
@@ -1084,11 +1083,11 @@ public abstract class Http2MultiplexTest<C extends Http2FrameCodec> {
         frameInboundWriter.writeInboundData(childChannel.stream().id(), bb("bar"), 0, false);
 
         // Add a handler which will request reads.
-        childChannel.pipeline().addFirst(new ChannelInboundHandlerAdapter() {
+        childChannel.pipeline().addFirst(new ChannelHandler() {
 
             @Override
-            public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
+            public void channelReadComplete(ChannelHandlerContext ctx) {
-                super.channelReadComplete(ctx);
+                ctx.fireChannelReadComplete();
                 if (triggerOnReadComplete) {
                     ctx.read();
                     ctx.read();

codec-http2/src/test/java/io/netty/handler/codec/http2/HttpToHttp2ConnectionHandlerTest.java

@@ -22,7 +22,6 @@ import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.ChannelPromise;

codec/src/main/java/io/netty/handler/codec/MessageToMessageDecoder.java

@@ -15,18 +15,16 @@
  */
 package io.netty.handler.codec;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerAdapter;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelPipeline;
 import io.netty.util.ReferenceCountUtil;
 import io.netty.util.ReferenceCounted;
 import io.netty.util.internal.TypeParameterMatcher;
 
-import java.util.List;
-
 /**
- * {@link ChannelInboundHandler} which decodes from one message to an other message.
+ * {@link ChannelHandler} which decodes from one message to an other message.
  *
  *
  * For example here is an implementation which decodes a {@link String} to an {@link Integer} which represent
@@ -49,7 +47,7 @@ import java.util.List;
  * {@link ReferenceCounted#release()} on decoded messages.
  *
  */
-public abstract class MessageToMessageDecoder<I> extends ChannelHandlerAdapter implements ChannelInboundHandler {
+public abstract class MessageToMessageDecoder<I> extends ChannelHandlerAdapter {
 
     private final TypeParameterMatcher matcher;
 
@@ -71,7 +69,7 @@ public abstract class MessageToMessageDecoder<I> extends ChannelHandlerAdapter i
 
     /**
      * Returns {@code true} if the given message should be handled. If {@code false} it will be passed to the next
-     * {@link ChannelInboundHandler} in the {@link ChannelPipeline}.
+     * {@link ChannelHandler} in the {@link ChannelPipeline}.
      */
     public boolean acceptInboundMessage(Object msg) throws Exception {
         return matcher.match(msg);

codec/src/test/java/io/netty/handler/codec/ByteToMessageDecoderTest.java

@@ -24,9 +24,7 @@ import io.netty.buffer.UnpooledByteBufAllocator;
 import io.netty.buffer.UnpooledHeapByteBuf;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelOutboundHandlerAdapter;
 import io.netty.channel.embedded.EmbeddedChannel;
-import org.junit.Ignore;
 import org.junit.Test;
 
 import java.util.concurrent.BlockingQueue;
@@ -433,13 +431,13 @@ public class ByteToMessageDecoderTest {
 
     @Test
     public void testDoesNotOverRead() {
-        class ReadInterceptingHandler extends ChannelOutboundHandlerAdapter {
+        class ReadInterceptingHandler implements ChannelHandler {
             private int readsTriggered;
 
             @Override
-            public void read(ChannelHandlerContext ctx) throws Exception {
+            public void read(ChannelHandlerContext ctx) {
                 readsTriggered++;
-                super.read(ctx);
+                ctx.read();
             }
         }
         ReadInterceptingHandler interceptor = new ReadInterceptingHandler();

example/src/main/java/io/netty/example/echo/EchoClientHandler.java

@@ -17,15 +17,15 @@ package io.netty.example.echo;
 
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 
 /**
  * Handler implementation for the echo client.  It initiates the ping-pong
  * traffic between the echo client and server by sending the first message to
  * the server.
  */
-public class EchoClientHandler implements ChannelInboundHandler {
+public class EchoClientHandler implements ChannelHandler {
 
     private final ByteBuf firstMessage;
 

example/src/main/java/io/netty/example/echo/EchoServerHandler.java

@@ -15,15 +15,15 @@
  */
 package io.netty.example.echo;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandler.Sharable;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 
 /**
  * Handler implementation for the echo server.
  */
 @Sharable
-public class EchoServerHandler implements ChannelInboundHandler {
+public class EchoServerHandler implements ChannelHandler {
 
     @Override
     public void channelRead(ChannelHandlerContext ctx, Object msg) {

example/src/main/java/io/netty/example/http2/helloworld/client/Http2ClientInitializer.java

@@ -15,8 +15,8 @@
 package io.netty.example.http2.helloworld.client;
 
 import io.netty.buffer.Unpooled;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.socket.SocketChannel;
@@ -134,7 +134,7 @@ public class Http2ClientInitializer extends ChannelInitializer<SocketChannel> {
     /**
      * A handler that triggers the cleartext upgrade to HTTP/2 by sending an initial HTTP request.
      */
-    private final class UpgradeRequestHandler implements ChannelInboundHandler {
+    private final class UpgradeRequestHandler implements ChannelHandler {
 
         @Override
         public void channelActive(ChannelHandlerContext ctx) throws Exception {
@@ -163,7 +163,7 @@ public class Http2ClientInitializer extends ChannelInitializer<SocketChannel> {
     /**
      * Class that logs any User Events triggered on this channel.
      */
-    private static class UserEventLogger implements ChannelInboundHandler {
+    private static class UserEventLogger implements ChannelHandler {
         @Override
         public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
             System.out.println("User Event Triggered: " + evt);

example/src/main/java/io/netty/example/http2/helloworld/frame/server/Http2ServerInitializer.java

@@ -16,8 +16,8 @@
 
 package io.netty.example.http2.helloworld.frame.server;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.SimpleChannelInboundHandler;
@@ -108,7 +108,7 @@ public class Http2ServerInitializer extends ChannelInitializer<SocketChannel> {
     /**
      * Class that logs any User Events triggered on this channel.
      */
-    private static class UserEventLogger implements ChannelInboundHandler {
+    private static class UserEventLogger implements ChannelHandler {
         @Override
         public void userEventTriggered(ChannelHandlerContext ctx, Object evt) {
             System.out.println("User Event Triggered: " + evt);

example/src/main/java/io/netty/example/http2/helloworld/multiplex/server/Http2ServerInitializer.java

@@ -16,8 +16,8 @@
 
 package io.netty.example.http2.helloworld.multiplex.server;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.SimpleChannelInboundHandler;
@@ -110,7 +110,7 @@ public class Http2ServerInitializer extends ChannelInitializer<SocketChannel> {
     /**
      * Class that logs any User Events triggered on this channel.
      */
-    private static class UserEventLogger implements ChannelInboundHandler {
+    private static class UserEventLogger implements ChannelHandler {
         @Override
         public void userEventTriggered(ChannelHandlerContext ctx, Object evt) {
             System.out.println("User Event Triggered: " + evt);

example/src/main/java/io/netty/example/http2/helloworld/server/Http2ServerInitializer.java

@@ -16,8 +16,8 @@
 
 package io.netty.example.http2.helloworld.server;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.SimpleChannelInboundHandler;
@@ -109,7 +109,7 @@ public class Http2ServerInitializer extends ChannelInitializer<SocketChannel> {
     /**
      * Class that logs any User Events triggered on this channel.
      */
-    private static class UserEventLogger implements ChannelInboundHandler {
+    private static class UserEventLogger implements ChannelHandler {
         @Override
         public void userEventTriggered(ChannelHandlerContext ctx, Object evt) {
             System.out.println("User Event Triggered: " + evt);

example/src/main/java/io/netty/example/localecho/LocalEchoServerHandler.java

@@ -15,10 +15,10 @@
  */
 package io.netty.example.localecho;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 
-public class LocalEchoServerHandler implements ChannelInboundHandler {
+public class LocalEchoServerHandler implements ChannelHandler {
 
     @Override
     public void channelRead(ChannelHandlerContext ctx, Object msg) {

example/src/main/java/io/netty/example/mqtt/heartBeat/MqttHeartBeatBrokerHandler.java

@@ -15,9 +15,9 @@
  */
 package io.netty.example.mqtt.heartBeat;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandler.Sharable;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandlerAdapter;
 import io.netty.handler.codec.mqtt.MqttConnAckMessage;
 import io.netty.handler.codec.mqtt.MqttConnAckVariableHeader;
 import io.netty.handler.codec.mqtt.MqttConnectReturnCode;
@@ -30,7 +30,7 @@ import io.netty.handler.timeout.IdleStateEvent;
 import io.netty.util.ReferenceCountUtil;
 
 @Sharable
-public final class MqttHeartBeatBrokerHandler extends ChannelInboundHandlerAdapter {
+public final class MqttHeartBeatBrokerHandler implements ChannelHandler {
 
     public static final MqttHeartBeatBrokerHandler INSTANCE = new MqttHeartBeatBrokerHandler();
 
@@ -38,7 +38,7 @@ public final class MqttHeartBeatBrokerHandler extends ChannelInboundHandlerAdapt
     }
 
     @Override
-    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
+    public void channelRead(ChannelHandlerContext ctx, Object msg) {
         MqttMessage mqttMessage = (MqttMessage) msg;
         System.out.println("Received MQTT message: " + mqttMessage);
         switch (mqttMessage.fixedHeader().messageType()) {
@@ -67,7 +67,7 @@ public final class MqttHeartBeatBrokerHandler extends ChannelInboundHandlerAdapt
     }
 
     @Override
-    public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
+    public void userEventTriggered(ChannelHandlerContext ctx, Object evt) {
         System.out.println("Channel heartBeat lost");
         if (evt instanceof IdleStateEvent && IdleState.READER_IDLE == ((IdleStateEvent) evt).state()) {
             ctx.close();
@@ -75,7 +75,7 @@ public final class MqttHeartBeatBrokerHandler extends ChannelInboundHandlerAdapt
     }
 
     @Override
-    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
         cause.printStackTrace();
         ctx.close();
     }

example/src/main/java/io/netty/example/mqtt/heartBeat/MqttHeartBeatClientHandler.java

@@ -15,8 +15,8 @@
  */
 package io.netty.example.mqtt.heartBeat;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandlerAdapter;
 import io.netty.handler.codec.mqtt.MqttConnectMessage;
 import io.netty.handler.codec.mqtt.MqttConnectPayload;
 import io.netty.handler.codec.mqtt.MqttConnectVariableHeader;
@@ -27,7 +27,7 @@ import io.netty.handler.codec.mqtt.MqttQoS;
 import io.netty.handler.timeout.IdleStateEvent;
 import io.netty.util.ReferenceCountUtil;
 
-public class MqttHeartBeatClientHandler extends ChannelInboundHandlerAdapter {
+public class MqttHeartBeatClientHandler implements ChannelHandler {
 
     private static final String PROTOCOL_NAME_MQTT_3_1_1 = "MQTT";
     private static final int PROTOCOL_VERSION_MQTT_3_1_1 = 4;
@@ -71,7 +71,7 @@ public class MqttHeartBeatClientHandler extends ChannelInboundHandlerAdapter {
             ctx.writeAndFlush(pingreqMessage);
             System.out.println("Sent PINGREQ");
         } else {
-            super.userEventTriggered(ctx, evt);
+            ctx.fireUserEventTriggered(evt);
         }
     }
 

example/src/main/java/io/netty/example/objectecho/ObjectEchoClientHandler.java

@@ -15,8 +15,8 @@
  */
 package io.netty.example.objectecho;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -26,7 +26,7 @@ import java.util.List;
  * ping-pong traffic between the object echo client and server by sending the
  * first message to the server.
  */
-public class ObjectEchoClientHandler implements ChannelInboundHandler {
+public class ObjectEchoClientHandler implements ChannelHandler {
 
     private final List<Integer> firstMessage;
 

example/src/main/java/io/netty/example/objectecho/ObjectEchoServerHandler.java

@@ -15,14 +15,14 @@
  */
 package io.netty.example.objectecho;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 
 /**
  * Handles both client-side and server-side handler depending on which
  * constructor was called.
  */
-public class ObjectEchoServerHandler implements ChannelInboundHandler {
+public class ObjectEchoServerHandler implements ChannelHandler {
 
     @Override
     public void channelRead(ChannelHandlerContext ctx, Object msg) {

example/src/main/java/io/netty/example/ocsp/OcspClientExample.java

@@ -22,7 +22,7 @@ import javax.net.ssl.SSLSession;
 import javax.security.cert.X509Certificate;
 
 import io.netty.buffer.Unpooled;
-import io.netty.channel.ChannelInboundHandler;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.MultithreadEventLoopGroup;
 import io.netty.channel.nio.NioHandler;
 import org.bouncycastle.asn1.ocsp.OCSPResponseStatus;
@@ -153,7 +153,7 @@ public class OcspClientExample {
         };
     }
 
-    private static class HttpClientHandler implements ChannelInboundHandler {
+    private static class HttpClientHandler implements ChannelHandler {
 
         private final String host;
 

example/src/main/java/io/netty/example/proxy/HexDumpProxyBackendHandler.java

@@ -17,10 +17,10 @@ package io.netty.example.proxy;
 
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 
-public class HexDumpProxyBackendHandler implements ChannelInboundHandler {
+public class HexDumpProxyBackendHandler implements ChannelHandler {
 
     private final Channel inboundChannel;
 

example/src/main/java/io/netty/example/proxy/HexDumpProxyFrontendHandler.java

@@ -20,11 +20,11 @@ import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelOption;
 
-public class HexDumpProxyFrontendHandler implements ChannelInboundHandler {
+public class HexDumpProxyFrontendHandler implements ChannelHandler {
 
     private final String remoteHost;
     private final int remotePort;

example/src/main/java/io/netty/example/sctp/SctpEchoClientHandler.java

@@ -17,8 +17,8 @@ package io.netty.example.sctp;
 
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.sctp.SctpMessage;
 
 /**
@@ -26,7 +26,7 @@ import io.netty.channel.sctp.SctpMessage;
  * traffic between the echo client and server by sending the first message to
  * the server.
  */
-public class SctpEchoClientHandler implements ChannelInboundHandler {
+public class SctpEchoClientHandler implements ChannelHandler {
 
     private final ByteBuf firstMessage;
 

example/src/main/java/io/netty/example/sctp/SctpEchoServerHandler.java

@@ -15,15 +15,15 @@
  */
 package io.netty.example.sctp;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandler.Sharable;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 
 /**
  * Handler implementation for the SCTP echo server.
  */
 @Sharable
-public class SctpEchoServerHandler implements ChannelInboundHandler {
+public class SctpEchoServerHandler implements ChannelHandler {
 
     @Override
     public void channelRead(ChannelHandlerContext ctx, Object msg) {

example/src/main/java/io/netty/example/socksproxy/DirectClientHandler.java

@@ -16,11 +16,11 @@
 package io.netty.example.socksproxy;
 
 import io.netty.channel.Channel;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.util.concurrent.Promise;
 
-public final class DirectClientHandler implements ChannelInboundHandler {
+public final class DirectClientHandler implements ChannelHandler {
 
     private final Promise<Channel> promise;
 

example/src/main/java/io/netty/example/socksproxy/RelayHandler.java

@@ -17,11 +17,11 @@ package io.netty.example.socksproxy;
 
 import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.util.ReferenceCountUtil;
 
-public final class RelayHandler implements ChannelInboundHandler {
+public final class RelayHandler implements ChannelHandler {
 
     private final Channel relayChannel;
 

handler-proxy/src/test/java/io/netty/handler/proxy/ProxyServer.java

@@ -25,7 +25,6 @@ import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.EventLoop;
@@ -229,7 +228,7 @@ abstract class ProxyServer {
             ctx.close();
         }
 
-        private final class BackendHandler implements ChannelInboundHandler {
+        private final class BackendHandler implements ChannelHandler {
 
             private final ChannelHandlerContext frontend;
 

handler/src/main/java/io/netty/handler/ipfilter/AbstractRemoteAddressFilter.java

@@ -18,8 +18,8 @@ package io.netty.handler.ipfilter;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 
 import java.net.SocketAddress;
 
@@ -35,7 +35,7 @@ import java.net.SocketAddress;
  * flexibility to respond to rejected (denied) connections. If you do not want to send a response, just have it return
  * null.  Take a look at {@link RuleBasedIpFilter} for details.
  */
-public abstract class AbstractRemoteAddressFilter<T extends SocketAddress> implements ChannelInboundHandler {
+public abstract class AbstractRemoteAddressFilter<T extends SocketAddress> implements ChannelHandler {
 
     @Override
     public void channelRegistered(ChannelHandlerContext ctx) throws Exception {

handler/src/main/java/io/netty/handler/logging/LoggingHandler.java

@@ -20,7 +20,6 @@ import io.netty.buffer.ByteBufHolder;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandler.Sharable;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelOutboundHandler;
 import io.netty.channel.ChannelPromise;
 import io.netty.util.internal.logging.InternalLogLevel;
 import io.netty.util.internal.logging.InternalLogger;
@@ -287,7 +286,7 @@ public class LoggingHandler implements ChannelHandler {
 
     /**
      * Formats an event and returns the formatted message.  This method is currently only used for formatting
-     * {@link ChannelOutboundHandler#connect(ChannelHandlerContext, SocketAddress, SocketAddress, ChannelPromise)}.
+     * {@link ChannelHandler#connect(ChannelHandlerContext, SocketAddress, SocketAddress, ChannelPromise)}.
      *
      * @param eventName the name of the event
      * @param firstArg  the first argument of the event

handler/src/main/java/io/netty/handler/ssl/ApplicationProtocolNegotiationHandler.java

@@ -18,8 +18,8 @@ package io.netty.handler.ssl;
 import static java.util.Objects.requireNonNull;
 
 import io.netty.channel.Channel;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelPipeline;
 import io.netty.util.internal.logging.InternalLogger;
@@ -60,7 +60,7 @@ import io.netty.util.internal.logging.InternalLoggerFactory;
  * }
  * </pre>
  */
-public abstract class ApplicationProtocolNegotiationHandler implements ChannelInboundHandler {
+public abstract class ApplicationProtocolNegotiationHandler implements ChannelHandler {
 
     private static final InternalLogger logger =
             InternalLoggerFactory.getInstance(ApplicationProtocolNegotiationHandler.class);

handler/src/main/java/io/netty/handler/ssl/SslMasterKeyHandler.java

@@ -16,8 +16,8 @@
 package io.netty.handler.ssl;
 
 import io.netty.buffer.ByteBufUtil;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandlerAdapter;
 import io.netty.util.internal.ReflectionUtil;
 import io.netty.util.internal.SystemPropertyUtil;
 import io.netty.util.internal.logging.InternalLogger;
@@ -35,7 +35,7 @@ import java.lang.reflect.Field;
  * This can be very useful, for instance the {@link WiresharkSslMasterKeyHandler} implementation will
  * log the secret & identifier in a format that is consumable by Wireshark -- allowing easy decryption of pcap/tcpdumps.
  */
-public abstract class SslMasterKeyHandler extends ChannelInboundHandlerAdapter {
+public abstract class SslMasterKeyHandler implements ChannelHandler {
 
     private static final InternalLogger logger = InternalLoggerFactory.getInstance(SslMasterKeyHandler.class);
 

handler/src/main/java/io/netty/handler/ssl/ocsp/OcspClientHandler.java

@@ -17,8 +17,8 @@ package io.netty.handler.ssl.ocsp;
 
 import static java.util.Objects.requireNonNull;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.handler.ssl.ReferenceCountedOpenSslContext;
 import io.netty.handler.ssl.ReferenceCountedOpenSslEngine;
 import io.netty.handler.ssl.SslHandshakeCompletionEvent;
@@ -33,7 +33,7 @@ import javax.net.ssl.SSLHandshakeException;
  * @see ReferenceCountedOpenSslEngine#getOcspResponse()
  */
 @UnstableApi
-public abstract class OcspClientHandler implements ChannelInboundHandler {
+public abstract class OcspClientHandler implements ChannelHandler {
 
     private final ReferenceCountedOpenSslEngine engine;
 

handler/src/main/java/io/netty/handler/traffic/AbstractTrafficShapingHandler.java

@@ -18,7 +18,6 @@ package io.netty.handler.traffic;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufHolder;
 import io.netty.channel.Channel;
-import io.netty.channel.ChannelDuplexHandler;
 import io.netty.channel.ChannelConfig;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;

handler/src/test/java/io/netty/handler/ssl/SslHandlerTest.java

@@ -23,7 +23,6 @@ import io.netty.buffer.ByteBufAllocator;
 import io.netty.buffer.Unpooled;
 import io.netty.buffer.UnpooledByteBufAllocator;
 import io.netty.channel.Channel;
-import io.netty.channel.ChannelDuplexHandler;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
 import io.netty.channel.ChannelHandler;
@@ -107,7 +106,7 @@ public class SslHandlerTest {
                 writeLatch.countDown();
             }
         };
-        EmbeddedChannel ch = new EmbeddedChannel(new ChannelDuplexHandler() {
+        EmbeddedChannel ch = new EmbeddedChannel(new ChannelHandler() {
             @Override
             public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) {
                 if (msg instanceof ByteBuf) {

microbench/src/main/java/io/netty/handler/codec/http2/Http2FrameWriterDataBenchmark.java

@@ -21,7 +21,6 @@ import io.netty.buffer.UnpooledByteBufAllocator;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelPromise;
 import io.netty.microbench.channel.EmbeddedChannelWriteReleaseHandlerContext;
 import io.netty.microbench.util.AbstractMicrobenchmark;

resolver-dns/src/main/java/io/netty/resolver/dns/DnsNameResolver.java

@@ -25,7 +25,6 @@ import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelOption;
 import io.netty.channel.ChannelPromise;
@@ -1177,7 +1176,7 @@ public class DnsNameResolver extends InetNameResolver {
         return dnsServerAddressStreamProvider.nameServerAddressStream(hostname);
     }
 
-    private final class DnsResponseHandler implements ChannelInboundHandler {
+    private final class DnsResponseHandler implements ChannelHandler {
 
         private final Promise<Channel> channelActivePromise;
 

resolver-dns/src/test/java/io/netty/resolver/dns/DnsNameResolverTest.java

@@ -20,8 +20,8 @@ import io.netty.buffer.ByteBufHolder;
 import io.netty.channel.AddressedEnvelope;
 import io.netty.channel.ChannelFactory;
 import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandlerAdapter;
 import io.netty.channel.EventLoop;
 import io.netty.channel.EventLoopGroup;
 import io.netty.channel.MultithreadEventLoopGroup;
@@ -2802,7 +2802,7 @@ public class DnsNameResolverTest {
             }
             resolver = builder.build();
             if (truncatedBecauseOfMtu) {
-                resolver.ch.pipeline().addFirst(new ChannelInboundHandlerAdapter() {
+                resolver.ch.pipeline().addFirst(new ChannelHandler() {
                     @Override
                     public void channelRead(ChannelHandlerContext ctx, Object msg) {
                         if (msg instanceof DatagramPacket) {

testsuite-autobahn/src/main/java/io/netty/testsuite/autobahn/AutobahnServerHandler.java

@@ -19,8 +19,8 @@ import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.handler.codec.http.DefaultFullHttpResponse;
 import io.netty.handler.codec.http.FullHttpResponse;
 import io.netty.handler.codec.http.HttpHeaderNames;
@@ -48,7 +48,7 @@ import static io.netty.handler.codec.http.HttpVersion.*;
 /**
  * Handles handshakes and messages
  */
-public class AutobahnServerHandler implements ChannelInboundHandler {
+public class AutobahnServerHandler implements ChannelHandler {
     private static final Logger logger = Logger.getLogger(AutobahnServerHandler.class.getName());
 
     private WebSocketServerHandshaker handshaker;

testsuite-http2/src/main/java/io/netty/testsuite/http2/Http2ServerInitializer.java

@@ -18,8 +18,8 @@ package io.netty.testsuite.http2;
 
 import static io.netty.util.internal.ObjectUtil.checkPositiveOrZero;
 
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.SimpleChannelInboundHandler;
@@ -96,7 +96,7 @@ public class Http2ServerInitializer extends ChannelInitializer<SocketChannel> {
     /**
      * Class that logs any User Events triggered on this channel.
      */
-    private static class UserEventLogger implements ChannelInboundHandler {
+    private static class UserEventLogger implements ChannelHandler {
         @Override
         public void userEventTriggered(ChannelHandlerContext ctx, Object evt) {
             System.out.println("User Event Triggered: " + evt);

testsuite/src/main/java/io/netty/testsuite/transport/socket/AbstractSocketReuseFdTest.java

@@ -22,8 +22,8 @@ import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandlerAdapter;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelOption;
 import io.netty.testsuite.transport.TestsuitePermutation;
@@ -110,7 +110,7 @@ public abstract class AbstractSocketReuseFdTest extends AbstractSocketTest {
         }
     }
 
-    static class ReuseFdHandler extends ChannelInboundHandlerAdapter {
+    static class ReuseFdHandler implements ChannelHandler {
         private static final String EXPECTED_PAYLOAD = "payload";
 
         private final Promise<Void> donePromise;

testsuite/src/main/java/io/netty/testsuite/transport/socket/DatagramConnectNotExistsTest.java

@@ -21,7 +21,6 @@ import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.testsuite.transport.TestsuitePermutation;
 import io.netty.util.CharsetUtil;
 import io.netty.util.NetUtil;

testsuite/src/main/java/io/netty/testsuite/transport/socket/ServerSocketSuspendTest.java

@@ -19,7 +19,6 @@ import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelOption;
 import io.netty.util.internal.SocketUtils;
 import org.junit.Ignore;
@@ -94,7 +93,7 @@ public class ServerSocketSuspendTest extends AbstractServerSocketTest {
     }
 
     @ChannelHandler.Sharable
-    private static final class AcceptedChannelCounter implements ChannelInboundHandler {
+    private static final class AcceptedChannelCounter implements ChannelHandler {
 
         final CountDownLatch latch;
 

testsuite/src/main/java/io/netty/testsuite/transport/socket/SocketAutoReadTest.java

@@ -22,8 +22,8 @@ import io.netty.buffer.ByteBufAllocator;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelConfig;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelOption;
 import io.netty.channel.RecvByteBufAllocator;
@@ -116,7 +116,7 @@ public class SocketAutoReadTest extends AbstractSocketTest {
         }
     }
 
-    private static final class AutoReadHandler implements ChannelInboundHandler {
+    private static final class AutoReadHandler implements ChannelHandler {
         private final AtomicInteger count = new AtomicInteger();
         private final CountDownLatch latch = new CountDownLatch(1);
         private final CountDownLatch latch2;

testsuite/src/main/java/io/netty/testsuite/transport/socket/SocketChannelNotYetConnectedTest.java

@@ -17,7 +17,6 @@ package io.netty.testsuite.transport.socket;
 
 import io.netty.bootstrap.Bootstrap;
 import io.netty.channel.ChannelHandler;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.socket.SocketChannel;
 import org.junit.Test;
 

testsuite/src/main/java/io/netty/testsuite/transport/socket/SocketCloseForciblyTest.java

@@ -20,7 +20,6 @@ import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.socket.SocketChannel;
 import org.junit.Test;
 

testsuite/src/main/java/io/netty/testsuite/transport/socket/SocketExceptionHandlingTest.java

@@ -19,8 +19,8 @@ import io.netty.bootstrap.Bootstrap;
 import io.netty.bootstrap.ServerBootstrap;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelOption;
 import io.netty.channel.ChannelPipeline;
@@ -83,7 +83,7 @@ public class SocketExceptionHandlingTest extends AbstractSocketTest {
         }
     }
 
-    private static class BuggyChannelHandler implements ChannelInboundHandler {
+    private static class BuggyChannelHandler implements ChannelHandler {
         @Override
         public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
             ReferenceCountUtil.release(msg);
@@ -91,7 +91,7 @@ public class SocketExceptionHandlingTest extends AbstractSocketTest {
         }
     }
 
-    private static class ExceptionHandler implements ChannelInboundHandler {
+    private static class ExceptionHandler implements ChannelHandler {
         final AtomicLong count = new AtomicLong();
         /**
          * We expect to get 1 call to {@link #exceptionCaught(ChannelHandlerContext, Throwable)}.

testsuite/src/main/java/io/netty/testsuite/transport/socket/SocketObjectEchoTest.java

@@ -18,8 +18,8 @@ package io.netty.testsuite.transport.socket;
 import io.netty.bootstrap.Bootstrap;
 import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.Channel;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelOption;
 import io.netty.handler.codec.serialization.ClassResolvers;
@@ -149,7 +149,7 @@ public class SocketObjectEchoTest extends AbstractSocketTest {
         }
     }
 
-    private static class EchoHandler implements ChannelInboundHandler {
+    private static class EchoHandler implements ChannelHandler {
         private final boolean autoRead;
         volatile Channel channel;
         final AtomicReference<Throwable> exception = new AtomicReference<>();

testsuite/src/main/java/io/netty/testsuite/transport/socket/SocketReadPendingTest.java

@@ -22,8 +22,8 @@ import io.netty.buffer.ByteBufAllocator;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelConfig;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelOption;
 import io.netty.channel.RecvByteBufAllocator;
@@ -101,7 +101,7 @@ public class SocketReadPendingTest extends AbstractSocketTest {
         }
     }
 
-    private static final class ReadPendingReadHandler implements ChannelInboundHandler {
+    private static final class ReadPendingReadHandler implements ChannelHandler {
         private final AtomicInteger count = new AtomicInteger();
         private final CountDownLatch latch = new CountDownLatch(1);
         private final CountDownLatch latch2 = new CountDownLatch(2);

testsuite/src/main/java/io/netty/testsuite/transport/socket/WriteBeforeRegisteredTest.java

@@ -17,8 +17,8 @@ package io.netty.testsuite.transport.socket;
 
 import io.netty.bootstrap.Bootstrap;
 import io.netty.buffer.Unpooled;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.socket.SocketChannel;
 import org.junit.Test;
 
@@ -42,7 +42,7 @@ public class WriteBeforeRegisteredTest extends AbstractClientSocketTest {
         }
     }
 
-    private static class TestHandler implements ChannelInboundHandler {
+    private static class TestHandler implements ChannelHandler {
         @Override
         public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
             cause.printStackTrace();

transport-native-epoll/src/test/java/io/netty/channel/epoll/EpollDomainSocketFdTest.java

@@ -21,7 +21,6 @@ import io.netty.channel.Channel;
 import io.netty.channel.ChannelFutureListener;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.unix.DomainSocketReadMode;
 import io.netty.channel.unix.FileDescriptor;
 import io.netty.testsuite.transport.TestsuitePermutation;

transport-native-epoll/src/test/java/io/netty/channel/epoll/EpollReuseAddrTest.java

@@ -20,9 +20,7 @@ import io.netty.bootstrap.Bootstrap;
 import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelHandler;
-import io.netty.channel.ChannelHandlerAdapter;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.handler.logging.LogLevel;
 import io.netty.handler.logging.LoggingHandler;
 import io.netty.util.NetUtil;
@@ -202,7 +200,7 @@ public class EpollReuseAddrTest {
     }
 
     @ChannelHandler.Sharable
-    private static class ServerSocketTestHandler implements ChannelInboundHandler {
+    private static class ServerSocketTestHandler implements ChannelHandler {
         private final AtomicBoolean accepted;
 
         ServerSocketTestHandler(AtomicBoolean accepted) {
@@ -217,7 +215,7 @@ public class EpollReuseAddrTest {
     }
 
     @ChannelHandler.Sharable
-    private static class DatagramSocketTestHandler implements ChannelInboundHandler {
+    private static class DatagramSocketTestHandler implements ChannelHandler {
         private final AtomicBoolean received;
 
         DatagramSocketTestHandler(AtomicBoolean received) {
@@ -232,5 +230,5 @@ public class EpollReuseAddrTest {
     }
 
     @ChannelHandler.Sharable
-    private static final class DummyHandler extends ChannelHandlerAdapter { }
+    private static final class DummyHandler implements ChannelHandler { }
 }

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueChannelConfigTest.java

@@ -18,7 +18,6 @@ package io.netty.channel.kqueue;
 import io.netty.bootstrap.Bootstrap;
 import io.netty.channel.ChannelException;
 import io.netty.channel.ChannelHandler;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelOption;
 import io.netty.channel.EventLoopGroup;
 import io.netty.channel.MultithreadEventLoopGroup;

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketFdTest.java

@@ -21,7 +21,6 @@ import io.netty.channel.Channel;
 import io.netty.channel.ChannelFutureListener;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.unix.DomainSocketReadMode;
 import io.netty.channel.unix.FileDescriptor;
 import io.netty.testsuite.transport.TestsuitePermutation;

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueServerSocketChannelConfigTest.java

@@ -17,7 +17,6 @@ package io.netty.channel.kqueue;
 
 import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.ChannelHandler;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.EventLoopGroup;
 import io.netty.channel.MultithreadEventLoopGroup;
 import org.junit.AfterClass;

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketChannelConfigTest.java

@@ -18,7 +18,6 @@ package io.netty.channel.kqueue;
 import io.netty.bootstrap.Bootstrap;
 import io.netty.channel.ChannelException;
 import io.netty.channel.ChannelHandler;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.EventLoopGroup;
 import io.netty.channel.MultithreadEventLoopGroup;
 import org.junit.After;

transport-sctp/src/main/java/io/netty/handler/codec/sctp/SctpMessageCompletionHandler.java

@@ -19,7 +19,7 @@ package io.netty.handler.codec.sctp;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.sctp.SctpMessage;
 import io.netty.handler.codec.MessageToMessageDecoder;
 
@@ -29,7 +29,7 @@ import java.util.Map;
 /**
  * {@link MessageToMessageDecoder} which will take care of handle fragmented {@link SctpMessage}s, so
  * only <strong>complete</strong> {@link SctpMessage}s will be forwarded to the next
- * {@link ChannelInboundHandler}.
+ * {@link ChannelHandler}.
  */
 public class SctpMessageCompletionHandler extends MessageToMessageDecoder<SctpMessage> {
     private final Map<Integer, ByteBuf> fragments = new HashMap<>();

transport/src/main/java/io/netty/bootstrap/ServerBootstrap.java

@@ -23,7 +23,6 @@ import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelOption;
 import io.netty.channel.ChannelPipeline;
@@ -210,7 +209,7 @@ public class ServerBootstrap extends AbstractBootstrap<ServerBootstrap, ServerCh
         return this;
     }
 
-    private static class ServerBootstrapAcceptor implements ChannelInboundHandler {
+    private static class ServerBootstrapAcceptor implements ChannelHandler {
 
         private final ChannelHandler childHandler;
         private final Entry<ChannelOption<?>, Object>[] childOptions;

transport/src/main/java/io/netty/channel/Channel.java

@@ -272,7 +272,7 @@ public interface Channel extends AttributeMap, ChannelOutboundInvoker, Comparabl
         void deregister(ChannelPromise promise);
 
         /**
-         * Schedules a read operation that fills the inbound buffer of the first {@link ChannelInboundHandler} in the
+         * Schedules a read operation that fills the inbound buffer of the first {@link ChannelHandler} in the
          * {@link ChannelPipeline}.  If there's already a pending read operation, this method does nothing.
          */
         void beginRead();

transport/src/main/java/io/netty/channel/ChannelConfig.java

@@ -125,7 +125,7 @@ public interface ChannelConfig {
      * {@link MaxMessagesRecvByteBufAllocator#maxMessagesPerRead()}.
      * <p>
      * Returns the maximum number of messages to read per read loop.
-     * a {@link ChannelInboundHandler#channelRead(ChannelHandlerContext, Object) channelRead()} event.
+     * a {@link ChannelHandler#channelRead(ChannelHandlerContext, Object) channelRead()} event.
      * If this value is greater than 1, an event loop might attempt to read multiple times to procure multiple messages.
      */
     @Deprecated

transport/src/main/java/io/netty/channel/ChannelHandlerContext.java

@@ -82,7 +82,7 @@ import java.nio.channels.Channels;
  * as how many times it is added to pipelines, regardless if it is added to the
  * same pipeline multiple times or added to different pipelines multiple times:
  * <pre>
- * public class FactorialHandler implements {@link ChannelInboundHandler} {
+ * public class FactorialHandler implements {@link ChannelHandler} {
  *
  *   private final {@link AttributeKey}&lt;{@link Integer}&gt; counter = {@link AttributeKey}.valueOf("counter");
  *

transport/src/main/java/io/netty/channel/ChannelInboundInvoker.java

@@ -20,8 +20,8 @@ public interface ChannelInboundInvoker {
     /**
      * A {@link Channel} was registered to its {@link EventLoop}.
      *
-     * This will result in having the  {@link ChannelInboundHandler#channelRegistered(ChannelHandlerContext)} method
+     * This will result in having the  {@link ChannelHandler#channelRegistered(ChannelHandlerContext)} method
-     * called of the next  {@link ChannelInboundHandler} contained in the  {@link ChannelPipeline} of the
+     * called of the next  {@link ChannelHandler} contained in the  {@link ChannelPipeline} of the
      * {@link Channel}.
      */
     ChannelInboundInvoker fireChannelRegistered();
@@ -29,8 +29,8 @@ public interface ChannelInboundInvoker {
     /**
      * A {@link Channel} was unregistered from its {@link EventLoop}.
      *
-     * This will result in having the  {@link ChannelInboundHandler#channelUnregistered(ChannelHandlerContext)} method
+     * This will result in having the  {@link ChannelHandler#channelUnregistered(ChannelHandlerContext)} method
-     * called of the next  {@link ChannelInboundHandler} contained in the  {@link ChannelPipeline} of the
+     * called of the next  {@link ChannelHandler} contained in the  {@link ChannelPipeline} of the
      * {@link Channel}.
      */
     ChannelInboundInvoker fireChannelUnregistered();
@@ -38,8 +38,8 @@ public interface ChannelInboundInvoker {
     /**
      * A {@link Channel} is active now, which means it is connected.
      *
-     * This will result in having the  {@link ChannelInboundHandler#channelActive(ChannelHandlerContext)} method
+     * This will result in having the  {@link ChannelHandler#channelActive(ChannelHandlerContext)} method
-     * called of the next  {@link ChannelInboundHandler} contained in the  {@link ChannelPipeline} of the
+     * called of the next  {@link ChannelHandler} contained in the  {@link ChannelPipeline} of the
      * {@link Channel}.
      */
     ChannelInboundInvoker fireChannelActive();
@@ -47,8 +47,8 @@ public interface ChannelInboundInvoker {
     /**
      * A {@link Channel} is inactive now, which means it is closed.
      *
-     * This will result in having the  {@link ChannelInboundHandler#channelInactive(ChannelHandlerContext)} method
+     * This will result in having the  {@link ChannelHandler#channelInactive(ChannelHandlerContext)} method
-     * called of the next  {@link ChannelInboundHandler} contained in the  {@link ChannelPipeline} of the
+     * called of the next  {@link ChannelHandler} contained in the  {@link ChannelPipeline} of the
      * {@link Channel}.
      */
     ChannelInboundInvoker fireChannelInactive();
@@ -56,8 +56,8 @@ public interface ChannelInboundInvoker {
     /**
      * A {@link Channel} received an {@link Throwable} in one of its inbound operations.
      *
-     * This will result in having the  {@link ChannelInboundHandler#exceptionCaught(ChannelHandlerContext, Throwable)}
+     * This will result in having the  {@link ChannelHandler#exceptionCaught(ChannelHandlerContext, Throwable)}
-     * method  called of the next  {@link ChannelInboundHandler} contained in the  {@link ChannelPipeline} of the
+     * method  called of the next  {@link ChannelHandler} contained in the  {@link ChannelPipeline} of the
      * {@link Channel}.
      */
     ChannelInboundInvoker fireExceptionCaught(Throwable cause);
@@ -65,8 +65,8 @@ public interface ChannelInboundInvoker {
     /**
      * A {@link Channel} received an user defined event.
      *
-     * This will result in having the  {@link ChannelInboundHandler#userEventTriggered(ChannelHandlerContext, Object)}
+     * This will result in having the  {@link ChannelHandler#userEventTriggered(ChannelHandlerContext, Object)}
-     * method  called of the next  {@link ChannelInboundHandler} contained in the  {@link ChannelPipeline} of the
+     * method  called of the next  {@link ChannelHandler} contained in the  {@link ChannelPipeline} of the
      * {@link Channel}.
      */
     ChannelInboundInvoker fireUserEventTriggered(Object event);
@@ -74,21 +74,21 @@ public interface ChannelInboundInvoker {
     /**
      * A {@link Channel} received a message.
      *
-     * This will result in having the {@link ChannelInboundHandler#channelRead(ChannelHandlerContext, Object)}
+     * This will result in having the {@link ChannelHandler#channelRead(ChannelHandlerContext, Object)}
-     * method  called of the next {@link ChannelInboundHandler} contained in the  {@link ChannelPipeline} of the
+     * method  called of the next {@link ChannelHandler} contained in the  {@link ChannelPipeline} of the
      * {@link Channel}.
      */
     ChannelInboundInvoker fireChannelRead(Object msg);
 
     /**
-     * Triggers an {@link ChannelInboundHandler#channelReadComplete(ChannelHandlerContext)}
+     * Triggers an {@link ChannelHandler#channelReadComplete(ChannelHandlerContext)}
-     * event to the next {@link ChannelInboundHandler} in the {@link ChannelPipeline}.
+     * event to the next {@link ChannelHandler} in the {@link ChannelPipeline}.
      */
     ChannelInboundInvoker fireChannelReadComplete();
 
     /**
-     * Triggers an {@link ChannelInboundHandler#channelWritabilityChanged(ChannelHandlerContext)}
+     * Triggers an {@link ChannelHandler#channelWritabilityChanged(ChannelHandlerContext)}
-     * event to the next {@link ChannelInboundHandler} in the {@link ChannelPipeline}.
+     * event to the next {@link ChannelHandler} in the {@link ChannelPipeline}.
      */
     ChannelInboundInvoker fireChannelWritabilityChanged();
 }

transport/src/main/java/io/netty/channel/ChannelInitializer.java

@@ -22,7 +22,7 @@ import io.netty.util.internal.logging.InternalLogger;
 import io.netty.util.internal.logging.InternalLoggerFactory;
 
 /**
- * A special {@link ChannelInboundHandler} which offers an easy way to initialize a {@link Channel} once it was
+ * A special {@link ChannelHandler} which offers an easy way to initialize a {@link Channel} once it was
  * registered to its {@link EventLoop}.
  *
  * Implementations are most often used in the context of {@link Bootstrap#handler(ChannelHandler)} ,
@@ -47,7 +47,7 @@ import io.netty.util.internal.logging.InternalLoggerFactory;
  * @param <C>   A sub-type of {@link Channel}
  */
 @Sharable
-public abstract class ChannelInitializer<C extends Channel> implements ChannelInboundHandler {
+public abstract class ChannelInitializer<C extends Channel> implements ChannelHandler {
 
     private static final InternalLogger logger = InternalLoggerFactory.getInstance(ChannelInitializer.class);
 

transport/src/main/java/io/netty/channel/ChannelOutboundInvoker.java

@@ -179,8 +179,8 @@ public interface ChannelOutboundInvoker {
      * The given {@link ChannelPromise} will be notified.
      * <p>
      * This will result in having the
-     * {@link ChannelOutboundHandler#close(ChannelHandlerContext, ChannelPromise)}
+     * {@link ChannelHandler#close(ChannelHandlerContext, ChannelPromise)}
-     * method called of the next {@link ChannelOutboundHandler} contained in the {@link ChannelPipeline} of the
+     * method called of the next {@link ChannelHandler} contained in the {@link ChannelPipeline} of the
      * {@link Channel}.
      */
     ChannelFuture close(ChannelPromise promise);
@@ -193,8 +193,8 @@ public interface ChannelOutboundInvoker {
      * The given {@link ChannelPromise} will be notified.
      * <p>
      * This will result in having the
-     * {@link ChannelOutboundHandler#register(ChannelHandlerContext, ChannelPromise)}
+     * {@link ChannelHandler#register(ChannelHandlerContext, ChannelPromise)}
-     * method called of the next {@link ChannelOutboundHandler} contained in the {@link ChannelPipeline} of the
+     * method called of the next {@link ChannelHandler} contained in the {@link ChannelPipeline} of the
      * {@link Channel}.
      */
     ChannelFuture register(ChannelPromise promise);

transport/src/main/java/io/netty/channel/CombinedChannelDuplexHandler.java

@@ -103,7 +103,7 @@ public class CombinedChannelDuplexHandler<I extends ChannelHandler, O extends Ch
     }
 
     /**
-     * Removes the {@link ChannelInboundHandler} that was combined in this {@link CombinedChannelDuplexHandler}.
+     * Removes the inbound {@link ChannelHandler} that was combined in this {@link CombinedChannelDuplexHandler}.
      */
     public final void removeInboundHandler() {
         checkAdded();
@@ -111,7 +111,7 @@ public class CombinedChannelDuplexHandler<I extends ChannelHandler, O extends Ch
     }
 
     /**
-     * Removes the {@link ChannelOutboundHandler} that was combined in this {@link CombinedChannelDuplexHandler}.
+     * Removes the outbound {@link ChannelHandler} that was combined in this {@link CombinedChannelDuplexHandler}.
      */
     public final void removeOutboundHandler() {
         checkAdded();

transport/src/main/java/io/netty/channel/DefaultChannelPipeline.java

@@ -54,7 +54,7 @@ public class DefaultChannelPipeline implements ChannelPipeline {
     private static final FastThreadLocal<Map<Class<?>, String>> nameCaches =
             new FastThreadLocal<Map<Class<?>, String>>() {
         @Override
-        protected Map<Class<?>, String> initialValue() throws Exception {
+        protected Map<Class<?>, String> initialValue() {
             return new WeakHashMap<>();
         }
     };
@@ -1011,7 +1011,7 @@ public class DefaultChannelPipeline implements ChannelPipeline {
 
     /**
      * Called once a {@link Throwable} hit the end of the {@link ChannelPipeline} without been handled by the user
-     * in {@link ChannelInboundHandler#exceptionCaught(ChannelHandlerContext, Throwable)}.
+     * in {@link ChannelHandler#exceptionCaught(ChannelHandlerContext, Throwable)}.
      */
     protected void onUnhandledInboundException(Throwable cause) {
         try {
@@ -1025,14 +1025,14 @@ public class DefaultChannelPipeline implements ChannelPipeline {
     }
 
     /**
-     * Called once the {@link ChannelInboundHandler#channelActive(ChannelHandlerContext)}event hit
+     * Called once the {@link ChannelHandler#channelActive(ChannelHandlerContext)}event hit
      * the end of the {@link ChannelPipeline}.
      */
     protected void onUnhandledInboundChannelActive() {
     }
 
     /**
-     * Called once the {@link ChannelInboundHandler#channelInactive(ChannelHandlerContext)} event hit
+     * Called once the {@link ChannelHandler#channelInactive(ChannelHandlerContext)} event hit
      * the end of the {@link ChannelPipeline}.
      */
     protected void onUnhandledInboundChannelInactive() {
@@ -1040,7 +1040,7 @@ public class DefaultChannelPipeline implements ChannelPipeline {
 
     /**
      * Called once a message hit the end of the {@link ChannelPipeline} without been handled by the user
-     * in {@link ChannelInboundHandler#channelRead(ChannelHandlerContext, Object)}. This method is responsible
+     * in {@link ChannelHandler#channelRead(ChannelHandlerContext, Object)}. This method is responsible
      * to call {@link ReferenceCountUtil#release(Object)} on the given msg at some point.
      */
     protected void onUnhandledInboundMessage(ChannelHandlerContext ctx, Object msg) {
@@ -1055,7 +1055,7 @@ public class DefaultChannelPipeline implements ChannelPipeline {
     }
 
     /**
-     * Called once the {@link ChannelInboundHandler#channelReadComplete(ChannelHandlerContext)} event hit
+     * Called once the {@link ChannelHandler#channelReadComplete(ChannelHandlerContext)} event hit
      * the end of the {@link ChannelPipeline}.
      */
     protected void onUnhandledInboundChannelReadComplete() {
@@ -1063,7 +1063,7 @@ public class DefaultChannelPipeline implements ChannelPipeline {
 
     /**
      * Called once an user event hit the end of the {@link ChannelPipeline} without been handled by the user
-     * in {@link ChannelInboundHandler#userEventTriggered(ChannelHandlerContext, Object)}. This method is responsible
+     * in {@link ChannelHandler#userEventTriggered(ChannelHandlerContext, Object)}. This method is responsible
      * to call {@link ReferenceCountUtil#release(Object)} on the given event at some point.
      */
     protected void onUnhandledInboundUserEventTriggered(Object evt) {
@@ -1073,7 +1073,7 @@ public class DefaultChannelPipeline implements ChannelPipeline {
     }
 
     /**
-     * Called once the {@link ChannelInboundHandler#channelWritabilityChanged(ChannelHandlerContext)} event hit
+     * Called once the {@link ChannelHandler#channelWritabilityChanged(ChannelHandlerContext)} event hit
      * the end of the {@link ChannelPipeline}.
      */
     protected void onUnhandledChannelWritabilityChanged() {
@@ -1096,7 +1096,7 @@ public class DefaultChannelPipeline implements ChannelPipeline {
     }
 
     // A special catch-all handler that handles both bytes and messages.
-    private static final class TailHandler implements ChannelInboundHandler {
+    private static final class TailHandler implements ChannelHandler {
 
         @Override
         public void channelRegistered(ChannelHandlerContext ctx) { }

transport/src/main/java/io/netty/channel/MaxBytesRecvByteBufAllocator.java

@@ -24,7 +24,7 @@ import java.util.Map.Entry;
 public interface MaxBytesRecvByteBufAllocator extends RecvByteBufAllocator {
     /**
      * Returns the maximum number of bytes to read per read loop.
-     * a {@link ChannelInboundHandler#channelRead(ChannelHandlerContext, Object) channelRead()} event.
+     * a {@link ChannelHandler#channelRead(ChannelHandlerContext, Object) channelRead()} event.
      * If this value is greater than 1, an event loop might attempt to read multiple times to procure bytes.
      */
     int maxBytesPerRead();
@@ -37,7 +37,7 @@ public interface MaxBytesRecvByteBufAllocator extends RecvByteBufAllocator {
 
     /**
      * Returns the maximum number of bytes to read per individual read operation.
-     * a {@link ChannelInboundHandler#channelRead(ChannelHandlerContext, Object) channelRead()} event.
+     * a {@link ChannelHandler#channelRead(ChannelHandlerContext, Object) channelRead()} event.
      * If this value is greater than 1, an event loop might attempt to read multiple times to procure bytes.
      */
     int maxBytesPerIndividualRead();

transport/src/main/java/io/netty/channel/MaxMessagesRecvByteBufAllocator.java

@@ -22,7 +22,7 @@ package io.netty.channel;
 public interface MaxMessagesRecvByteBufAllocator extends RecvByteBufAllocator {
     /**
      * Returns the maximum number of messages to read per read loop.
-     * a {@link ChannelInboundHandler#channelRead(ChannelHandlerContext, Object) channelRead()} event.
+     * a {@link ChannelHandler#channelRead(ChannelHandlerContext, Object) channelRead()} event.
      * If this value is greater than 1, an event loop might attempt to read multiple times to procure multiple messages.
      */
     int maxMessagesPerRead();

transport/src/main/java/io/netty/channel/SimpleChannelInboundHandler.java

@@ -19,7 +19,7 @@ import io.netty.util.ReferenceCountUtil;
 import io.netty.util.internal.TypeParameterMatcher;
 
 /**
- * {@link ChannelInboundHandler} which allows to explicit only handle a specific type of messages.
+ * {@link ChannelHandler} which allows to explicit only handle a specific type of messages.
  *
  * For example here is an implementation which only handle {@link String} messages.
  *
@@ -39,7 +39,7 @@ import io.netty.util.internal.TypeParameterMatcher;
  * {@link ReferenceCountUtil#release(Object)}. In this case you may need to use
  * {@link ReferenceCountUtil#retain(Object)} if you pass the object to the next handler in the {@link ChannelPipeline}.
  */
-public abstract class SimpleChannelInboundHandler<I> implements ChannelInboundHandler {
+public abstract class SimpleChannelInboundHandler<I> implements ChannelHandler {
 
     private final TypeParameterMatcher matcher;
     private final boolean autoRelease;
@@ -83,7 +83,7 @@ public abstract class SimpleChannelInboundHandler<I> implements ChannelInboundHa
 
     /**
      * Returns {@code true} if the given message should be handled. If {@code false} it will be passed to the next
-     * {@link ChannelInboundHandler} in the {@link ChannelPipeline}.
+     * {@link ChannelHandler} in the {@link ChannelPipeline}.
      */
     public boolean acceptInboundMessage(Object msg) throws Exception {
         return matcher.match(msg);

transport/src/main/java/io/netty/channel/SimpleUserEventChannelHandler.java

@@ -19,7 +19,7 @@ import io.netty.util.ReferenceCountUtil;
 import io.netty.util.internal.TypeParameterMatcher;
 
 /**
- * {@link ChannelInboundHandler} which allows to conveniently only handle a specific type of user events.
+ * {@link ChannelHandler} which allows to conveniently only handle a specific type of user events.
  *
  * For example, here is an implementation which only handle {@link String} user events.
  *
@@ -39,7 +39,7 @@ import io.netty.util.internal.TypeParameterMatcher;
  * {@link ReferenceCountUtil#release(Object)}. In this case you may need to use
  * {@link ReferenceCountUtil#retain(Object)} if you pass the object to the next handler in the {@link ChannelPipeline}.
  */
-public abstract class SimpleUserEventChannelHandler<I> implements ChannelInboundHandler {
+public abstract class SimpleUserEventChannelHandler<I> implements ChannelHandler {
 
     private final TypeParameterMatcher matcher;
     private final boolean autoRelease;
@@ -83,7 +83,7 @@ public abstract class SimpleUserEventChannelHandler<I> implements ChannelInbound
 
     /**
      * Returns {@code true} if the given user event should be handled. If {@code false} it will be passed to the next
-     * {@link ChannelInboundHandler} in the {@link ChannelPipeline}.
+     * {@link ChannelHandler} in the {@link ChannelPipeline}.
      */
     protected boolean acceptEvent(Object evt) throws Exception {
         return matcher.match(evt);

transport/src/main/java/io/netty/channel/group/ChannelGroup.java

@@ -21,8 +21,8 @@ import io.netty.buffer.ByteBufHolder;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelId;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.EventLoop;
 import io.netty.channel.ServerChannel;
 import io.netty.util.CharsetUtil;
@@ -82,7 +82,7 @@ import java.util.Set;
  *     <strong>allChannels.close().awaitUninterruptibly();</strong>
  * }
  *
- * public class MyHandler implements {@link ChannelInboundHandler} {
+ * public class MyHandler implements {@link ChannelHandler} {
  *     {@code @Override}
  *     public void channelActive({@link ChannelHandlerContext} ctx) {
  *         // closed on shutdown.

transport/src/main/java/io/netty/channel/socket/ChannelInputShutdownEvent.java

@@ -16,11 +16,11 @@
 package io.netty.channel.socket;
 
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
+import io.netty.channel.ChannelHandler;
 
 /**
  * Special event which will be fired and passed to the
- * {@link ChannelInboundHandler#userEventTriggered(ChannelHandlerContext, Object)} methods once the input of
+ * {@link ChannelHandler#userEventTriggered(ChannelHandlerContext, Object)} methods once the input of
  * a {@link SocketChannel} was shutdown and the {@link SocketChannelConfig#isAllowHalfClosure()} method returns
  * {@code true}.
  */

transport/src/main/java/io/netty/channel/socket/ChannelOutputShutdownEvent.java

@@ -16,12 +16,12 @@
 package io.netty.channel.socket;
 
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
+import io.netty.channel.ChannelHandler;
 import io.netty.util.internal.UnstableApi;
 
 /**
  * Special event which will be fired and passed to the
- * {@link ChannelInboundHandler#userEventTriggered(ChannelHandlerContext, Object)} methods once the output of
+ * {@link ChannelHandler#userEventTriggered(ChannelHandlerContext, Object)} methods once the output of
  * a {@link SocketChannel} was shutdown.
  */
 @UnstableApi

transport/src/main/java/io/netty/channel/socket/SocketChannelConfig.java

@@ -18,7 +18,7 @@ package io.netty.channel.socket;
 import io.netty.buffer.ByteBufAllocator;
 import io.netty.channel.ChannelConfig;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelOption;
 import io.netty.channel.MessageSizeEstimator;
 import io.netty.channel.RecvByteBufAllocator;
@@ -152,7 +152,7 @@ public interface SocketChannelConfig extends ChannelConfig {
      * Sets whether the channel should not close itself when its remote peer shuts down output to
      * make the connection half-closed.  If {@code true} the connection is not closed when the
      * remote peer shuts down output. Instead,
-     * {@link ChannelInboundHandler#userEventTriggered(ChannelHandlerContext, Object)}
+     * {@link ChannelHandler#userEventTriggered(ChannelHandlerContext, Object)}
      * is invoked with a {@link ChannelInputShutdownEvent} object. If {@code false}, the connection
      * is closed automatically.
      */

transport/src/test/java/io/netty/bootstrap/ServerBootstrapTest.java

@@ -17,7 +17,6 @@ package io.netty.bootstrap;
 
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelHandler;
-import io.netty.channel.ChannelHandlerAdapter;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.MultithreadEventLoopGroup;
@@ -47,7 +46,7 @@ public class ServerBootstrapTest {
             sb.channel(LocalServerChannel.class)
               .group(group)
               .childHandler(new ChannelHandler() { })
-              .handler(new ChannelHandlerAdapter() {
+              .handler(new ChannelHandler() {
                   @Override
                   public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
                       try {

transport/src/test/java/io/netty/channel/ChannelInitializerTest.java

@@ -251,7 +251,7 @@ public class ChannelInitializerTest {
         }
     }
 
-    private static final class InspectableHandler extends ChannelDuplexHandler {
+    private static final class InspectableHandler implements ChannelHandler {
         final AtomicInteger channelRegisteredCount = new AtomicInteger(0);
 
         @Override

transport/src/test/java/io/netty/channel/CombinedChannelDuplexHandlerTest.java

@@ -191,7 +191,7 @@ public class CombinedChannelDuplexHandlerTest {
 
         CombinedChannelDuplexHandler<ChannelHandler, ChannelHandler> handler =
                 new CombinedChannelDuplexHandler<>(
-                        inboundHandler, new ChannelOutboundHandler() { });
+                        inboundHandler, new ChannelHandler() { });
 
         EmbeddedChannel channel = new EmbeddedChannel(handler);
         channel.pipeline().fireChannelWritabilityChanged();
@@ -359,9 +359,9 @@ public class CombinedChannelDuplexHandlerTest {
             }
         };
         EmbeddedChannel ch = new EmbeddedChannel(outboundHandler,
-                new CombinedChannelDuplexHandler<ChannelInboundHandler, ChannelOutboundHandler>(
+                new CombinedChannelDuplexHandler<ChannelHandler, ChannelHandler>(
-                        new ChannelInboundHandler() {
+                        new ChannelHandler() {
-                        }, new ChannelOutboundHandler() { }));
+                        }, new ChannelHandler() { }));
         ChannelPipeline pipeline = ch.pipeline();
 
         ChannelPromise promise = ch.newPromise();
@@ -392,7 +392,7 @@ public class CombinedChannelDuplexHandlerTest {
 
     @Test(expected = IllegalStateException.class)
     public void testNotSharable() {
-        new CombinedChannelDuplexHandler<ChannelInboundHandler, ChannelOutboundHandler>() {
+        new CombinedChannelDuplexHandler<ChannelHandler, ChannelHandler>() {
             @Override
             public boolean isSharable() {
                 return true;

transport/src/test/java/io/netty/channel/DefaultChannelPipelineTest.java

@@ -146,7 +146,7 @@ public class DefaultChannelPipelineTest {
         assertTrue(handler.called);
     }
 
-    private static final class StringInboundHandler implements ChannelInboundHandler {
+    private static final class StringInboundHandler implements ChannelHandler {
         boolean called;
 
         @Override
@@ -946,7 +946,7 @@ public class DefaultChannelPipelineTest {
         EmbeddedChannel channel = new EmbeddedChannel(true);
         ChannelPipeline pipeline = channel.pipeline();
 
-        final class SkipHandler implements ChannelInboundHandler, ChannelOutboundHandler {
+        final class SkipHandler implements ChannelHandler {
             private int state = 2;
             private Error errorRef;
 
@@ -1100,7 +1100,7 @@ public class DefaultChannelPipelineTest {
             }
         }
 
-        final class OutboundCalledHandler implements ChannelOutboundHandler {
+        final class OutboundCalledHandler implements ChannelHandler {
             private static final int MASK_BIND = 1;
             private static final int MASK_CONNECT = 1 << 1;
             private static final int MASK_DISCONNECT = 1 << 2;
@@ -1197,7 +1197,7 @@ public class DefaultChannelPipelineTest {
             }
         }
 
-        final class InboundCalledHandler implements ChannelInboundHandler {
+        final class InboundCalledHandler implements ChannelHandler {
 
             private static final int MASK_CHANNEL_REGISTER = 1;
             private static final int MASK_CHANNEL_UNREGISTER = 1 << 1;
@@ -1463,7 +1463,7 @@ public class DefaultChannelPipelineTest {
         }
     }
 
-    private static final class CheckExceptionHandler implements ChannelInboundHandler {
+    private static final class CheckExceptionHandler implements ChannelHandler {
         private final Throwable expected;
         private final Promise<Void> promise;
 
@@ -1492,7 +1492,7 @@ public class DefaultChannelPipelineTest {
         fail("handler was not one of the expected handlers");
     }
 
-    private static final class CheckOrderHandler implements ChannelInboundHandler {
+    private static final class CheckOrderHandler implements ChannelHandler {
         private final Queue<CheckOrderHandler> addedQueue;
         private final Queue<CheckOrderHandler> removedQueue;
         private final AtomicReference<Throwable> error = new AtomicReference<>();

transport/src/test/java/io/netty/channel/PendingWriteQueueTest.java

@@ -193,7 +193,7 @@ public class PendingWriteQueueTest {
 
     private static EmbeddedChannel newChannel() {
         // Add a handler so we can access a ChannelHandlerContext via the ChannelPipeline.
-        return new EmbeddedChannel(new ChannelHandlerAdapter() { });
+        return new EmbeddedChannel(new ChannelHandler() { });
     }
 
     @Test

transport/src/test/java/io/netty/channel/SimpleUserEventChannelHandlerTest.java

@@ -85,7 +85,7 @@ public class SimpleUserEventChannelHandlerTest {
         }
     }
 
-    static final class AllEventCatcher implements ChannelInboundHandler {
+    static final class AllEventCatcher implements ChannelHandler {
 
         public List<Object> caughtEvents;
 

transport/src/test/java/io/netty/channel/embedded/EmbeddedChannelTest.java

@@ -40,7 +40,6 @@ import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
 import io.netty.channel.ChannelHandler;
-import io.netty.channel.ChannelHandlerAdapter;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.ChannelId;
 import io.netty.channel.ChannelInitializer;
@@ -148,7 +147,7 @@ public class EmbeddedChannelTest {
     public void testHandlerAddedExecutedInEventLoop() throws Throwable {
         final CountDownLatch latch = new CountDownLatch(1);
         final AtomicReference<Throwable> error = new AtomicReference<>();
-        final ChannelHandler handler = new ChannelHandlerAdapter() {
+        final ChannelHandler handler = new ChannelHandler() {
             @Override
             public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
                 try {

transport/src/test/java/io/netty/channel/local/LocalTransportThreadModelTest2.java

@@ -19,9 +19,9 @@ import io.netty.bootstrap.Bootstrap;
 import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandler.Sharable;
 import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelInboundHandler;
 import io.netty.channel.MultithreadEventLoopGroup;
 import io.netty.util.ReferenceCountUtil;
 import org.junit.Test;
@@ -90,7 +90,7 @@ public class LocalTransportThreadModelTest2 {
     }
 
     @Sharable
-    static class LocalHandler implements ChannelInboundHandler {
+    static class LocalHandler implements ChannelHandler {
         private final String name;
 
         public volatile ChannelFuture lastWriteFuture;