Merge branch 'master' of https://github.com/waylau/netty-4-user-guide-demos

Author: waylau

netty4-demos/src/main/java/com/waylau/netty/demo/pojo/MessageToByteTimeEncoder.java

@@ -0,0 +1,17 @@
+package com.waylau.netty.demo.pojo;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.MessageToByteEncoder;
+
+/**
+ * @author wangjun
+ * @date 2020-08-08
+ */
+public class MessageToByteTimeEncoder extends MessageToByteEncoder<UnixTime> {
+
+    @Override
+    protected void encode(ChannelHandlerContext ctx, UnixTime msg, ByteBuf out) {
+        out.writeInt((int)msg.value());
+    }
+}

netty4-demos/src/main/java/com/waylau/netty/demo/pojo/TimeClient.java

@@ -0,0 +1,42 @@
+package com.waylau.netty.demo.pojo;
+
+import io.netty.bootstrap.Bootstrap;
+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.NioSocketChannel;
+
+public class TimeClient {
+
+	public static void main(String[] args) throws Exception {
+
+		String host = "127.0.0.1";// args[0];
+        int port = 8080;//Integer.parseInt(args[1]);
+        EventLoopGroup workerGroup = new NioEventLoopGroup();
+
+        try {
+            Bootstrap b = new Bootstrap(); // (1)
+            b.group(workerGroup); // (2)
+            b.channel(NioSocketChannel.class); // (3)
+            b.option(ChannelOption.SO_KEEPALIVE, true); // (4)
+            b.handler(new ChannelInitializer<SocketChannel>() {
+                @Override
+                public void initChannel(SocketChannel ch) throws Exception {
+                    ch.pipeline().addLast(new TimeDecoder());
+                    ch.pipeline().addLast(new TimeClientHandler());
+                }
+            });
+
+            // 启动客户端
+            ChannelFuture f = b.connect(host, port).sync(); // (5)
+
+            // 等待连接关闭
+            f.channel().closeFuture().sync();
+        } finally {
+            workerGroup.shutdownGracefully();
+        }
+	}
+}

netty4-demos/src/main/java/com/waylau/netty/demo/pojo/TimeClientHandler.java

@@ -0,0 +1,18 @@
+package com.waylau.netty.demo.pojo;
+
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+
+/**
+ * @author wj89757
+ * @date 2020-08-08
+ */
+public class TimeClientHandler extends ChannelInboundHandlerAdapter{
+
+    @Override
+    public void channelRead(ChannelHandlerContext ctx, Object msg) {
+        UnixTime m = (UnixTime) msg;
+        System.out.println(m);
+        ctx.close();
+    }
+}

netty4-demos/src/main/java/com/waylau/netty/demo/pojo/TimeDecoder.java

@@ -0,0 +1,23 @@
+package com.waylau.netty.demo.pojo;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.ByteToMessageDecoder;
+
+import java.util.List;
+
+/**
+ * TimeDecoder 处理数据拆分的问题
+ * @author wj89757
+ * @date 2020-08-08
+ */
+public class TimeDecoder extends ByteToMessageDecoder {
+
+    @Override
+    protected void decode(ChannelHandlerContext channelHandlerContext, ByteBuf byteBuf, List<Object> list) throws Exception {
+        if (byteBuf.readableBytes() < 4) {
+            return;
+        }
+        list.add(new UnixTime(byteBuf.readUnsignedInt()));
+    }
+}

netty4-demos/src/main/java/com/waylau/netty/demo/pojo/TimeEncoder.java

@@ -0,0 +1,25 @@
+package com.waylau.netty.demo.pojo;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelOutboundHandlerAdapter;
+import io.netty.channel.ChannelPromise;
+
+/**
+ * @author wj89757
+ * @date 2020-08-08
+ */
+public class TimeEncoder extends ChannelOutboundHandlerAdapter {
+    /**
+     * 第一，通过 ChannelPromise，当编码后的数据被写到了通道上 Netty 可以通过这个对象标记是成功还是失败。
+     * 第二， 我们不需要调用 cxt.flush()。因为处理器已经单独分离出了一个方法 void flush(ChannelHandlerContext cxt),
+     * 如果像自己实现 flush() 方法内容可以自行覆盖这个方法。
+     */
+    @Override
+    public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) {
+        UnixTime m = (UnixTime) msg;
+        ByteBuf encoded = ctx.alloc().buffer(4);
+        encoded.writeInt((int)m.value());
+        ctx.write(encoded, promise);  // (1)
+    }
+}

netty4-demos/src/main/java/com/waylau/netty/demo/pojo/TimeServer.java

@@ -0,0 +1,61 @@
+package com.waylau.netty.demo.pojo;
+
+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;
+
+/**
+ * 时间服务器
+ */
+public class TimeServer {
+
+    private int port;
+
+    public TimeServer(int port) {
+        this.port = port;
+    }
+
+    public void run() throws Exception {
+        EventLoopGroup bossGroup = new NioEventLoopGroup(); // (1)
+        EventLoopGroup workerGroup = new NioEventLoopGroup();
+        try {
+            ServerBootstrap b = new ServerBootstrap(); // (2)
+            b.group(bossGroup, workerGroup)
+             .channel(NioServerSocketChannel.class) // (3)
+             .childHandler(new ChannelInitializer<SocketChannel>() { // (4)
+                 @Override
+                 public void initChannel(SocketChannel ch) throws Exception {
+                 ch.pipeline().addLast(new TimeEncoder());
+                 ch.pipeline().addLast(new TimeServerHandler());
+                 }
+             })
+             .option(ChannelOption.SO_BACKLOG, 128)          // (5)
+             .childOption(ChannelOption.SO_KEEPALIVE, true); // (6)
+
+            // 绑定端口，开始接收进来的连接
+            ChannelFuture f = b.bind(port).sync(); // (7)
+
+            // 等待服务器  socket 关闭 。
+            // 在这个例子中，这不会发生，但你可以优雅地关闭你的服务器。
+            f.channel().closeFuture().sync();
+        } finally {
+            workerGroup.shutdownGracefully();
+            bossGroup.shutdownGracefully();
+        }
+    }
+
+    public static void main(String[] args) throws Exception {
+        int port;
+        if (args.length > 0) {
+            port = Integer.parseInt(args[0]);
+        } else {
+            port = 8080;
+        }
+        new TimeServer(port).run();
+    }
+}

netty4-demos/src/main/java/com/waylau/netty/demo/pojo/TimeServerHandler.java

@@ -0,0 +1,20 @@
+package com.waylau.netty.demo.pojo;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+
+/**
+ * @author wj89757
+ * @date 2020-08-08
+ */
+public class TimeServerHandler extends ChannelInboundHandlerAdapter {
+
+    @Override
+    public void channelActive(ChannelHandlerContext ctx) throws Exception {
+        ChannelFuture f = ctx.writeAndFlush(new UnixTime());
+        f.addListener(ChannelFutureListener.CLOSE);
+    }
+}

netty4-demos/src/main/java/com/waylau/netty/demo/pojo/UnixTime.java

@@ -0,0 +1,28 @@
+package com.waylau.netty.demo.pojo;
+
+import java.util.Date;
+
+/**
+ * @author wj89757
+ * @date 2020-08-08
+ */
+public class UnixTime {
+    private final long value;
+
+    public UnixTime() {
+        this(System.currentTimeMillis() / 1000L + 2208988800L);
+    }
+
+    public UnixTime(long value) {
+        this.value = value;
+    }
+
+    public long value() {
+        return value;
+    }
+
+    @Override
+    public String toString() {
+        return new Date((value() - 2208988800L) * 1000L).toString();
+    }
+}