Example Code for Exceptions in Netty (#3406)

* added updated example codes

* updated example code StringToCharStream

* deleted StringToCharStream.java locally

* removed redundant file

* added code for apache commons collection SetUtils

* refactored example code

* added example code for bytebuddy

* added example code for PCollections

* update pom

* refactored tests for PCollections

* spring security xml config

* spring security xml config

* remove redundant comment

* example code for apache-shiro

* updated example code for Vavr Collections

* updated Vavr's Collection example

* updated Vavr Collection file

* updated example code for Apache Shiro

* updated Vavr Collections example

* added example code for N1QL

* update example code for N1QL

* added integration test for N1QL

* update N1QL Example code

* update the N1QL example Code

* rename module to couchbase

* rename module to couchbase

* change module name in parent module and pom

* added cas-server module

* added cas secured app for Spring SSO with CAS

* refactor cas modules into cas folder

* updated files

* removed redundant files

* refactor the config for cas-server

* added sql file to generate tables and database

* added source code for VRaptor

* update source code for VRaptor article

* update pom and reformat code

* add example code for BAEL-1439

* updated code for netty exceptions

libraries/src/main/java/com/baeldung/netty/ChannelHandlerA.java

@@ -0,0 +1,22 @@
+package com.baeldung.netty;
+
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+
+import java.util.logging.Logger;
+
+public class ChannelHandlerA extends ChannelInboundHandlerAdapter {
+
+    private Logger logger = Logger.getLogger(getClass().getName());
+
+    @Override
+    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
+        throw new Exception("Ooops");
+    }
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        logger.info("Exception Occurred in ChannelHandler A");
+        ctx.fireExceptionCaught(cause);
+    }
+}

libraries/src/main/java/com/baeldung/netty/ChannelHandlerB.java

@@ -0,0 +1,20 @@
+package com.baeldung.netty;
+
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+
+import java.util.logging.Logger;
+
+
+public class ChannelHandlerB extends ChannelInboundHandlerAdapter {
+
+    private Logger logger = Logger.getLogger(getClass().getName());
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        logger.info("Exception Handled in ChannelHandler B");
+        logger.info(cause.getLocalizedMessage());
+        //do more exception handling
+        ctx.close();
+    }
+}

libraries/src/main/java/com/baeldung/netty/NettyServerB.java

@@ -0,0 +1,47 @@
+package com.baeldung.netty;
+
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelInitializer;
+import io.netty.channel.ChannelOption;
+import io.netty.channel.EventLoopGroup;
+import io.netty.channel.nio.NioEventLoopGroup;
+import io.netty.channel.socket.SocketChannel;
+import io.netty.channel.socket.nio.NioServerSocketChannel;
+
+public class NettyServerB  {
+
+    private int port;
+
+    private NettyServerB(int port) {
+        this.port = port;
+    }
+
+    private void run() throws Exception {
+
+        EventLoopGroup bossGroup = new NioEventLoopGroup();
+        EventLoopGroup workerGroup = new NioEventLoopGroup();
+
+        try {
+            ServerBootstrap b = new ServerBootstrap();
+            b.group(bossGroup, workerGroup)
+                .channel(NioServerSocketChannel.class)
+                .childHandler(new ChannelInitializer<SocketChannel>() {
+                    public void initChannel(SocketChannel ch) throws Exception {
+                        ch.pipeline().addLast(new ChannelHandlerA(), new ChannelHandlerB());
+                    }
+                })
+                .option(ChannelOption.SO_BACKLOG, 128)
+                .childOption(ChannelOption.SO_KEEPALIVE, true);
+            ChannelFuture f = b.bind(port).sync(); // (7)
+            f.channel().closeFuture().sync();
+        } finally {
+            workerGroup.shutdownGracefully();
+            bossGroup.shutdownGracefully();
+        }
+    }
+
+    public static void main(String[] args) throws Exception {
+        new NettyServerB(8080).run();
+    }
+}