Vert.x-tcp-eventbus-bridge Java代码示例

关于 Vert.x-tcp-eventbus-bridge 的详细用法，Vert.x 的官方文档（官方文档1、官方文档2）都写得很简单，简单得还是让人搞不懂如何使用。

从网上找到了一篇介绍如何使用的文章：Vert.x TCP EventBus Bridge补遗。该项目中的例子源码在 github 上。看了源码之后，发现是一个 groovy项目。于是就将例子用 Java 代码重新写了下。总共有如下几个文件：

1. pom 文件

    4.0.0

    io.example
    vertx-example
    1.0-SNAPSHOT

    
        UTF-8
		3.4.2
        io.vertx.core.Launcher
        io.example.MainVerticle
        20.0
    

    
        
            io.vertx
            vertx-core
            ${vertx.version}
        
        
            io.vertx
            vertx-web
            ${vertx.version}
        
        
            io.vertx
            vertx-tcp-eventbus-bridge
            ${vertx.version}
        
        
            com.google.guava
            guava
            ${guava.version}
        
    

    
        
            
                org.apache.maven.plugins
                maven-compiler-plugin
                3.7.0
                
                    1.8
                    1.8
                
            
			
			
				org.apache.maven.plugins
                maven-shade-plugin
                3.1.1
				
					
						package
						
							shade
						
						
							
								
									
										${main.class}
                                        ${main.verticle}
									
								
							
							
							${project.build.directory}/${project.artifactId}-${project.version}-prod.jar
						
					
				
			
        
    

2. MainVerticle

package io.example;

import io.example.tcp.TcpClientVerticle;
import io.example.tcp.TcpServerVerticle;
import io.vertx.core.AbstractVerticle;

/**
 *
 */
public class MainVerticle extends AbstractVerticle {
    @Override
    public void start() throws Exception {
        // TCP EventBus Bridge
        vertx.deployVerticle(TcpServerVerticle.class.getName());
        vertx.deployVerticle(TcpClientVerticle.class.getName());
    }
}

3. TcpServerVerticle

package io.example.tcp;

import io.vertx.core.AbstractVerticle;
import io.vertx.core.Future;
import io.vertx.ext.bridge.BridgeOptions;
import io.vertx.ext.bridge.PermittedOptions;
import io.vertx.ext.eventbus.bridge.tcp.TcpEventBusBridge;

public class TcpServerVerticle extends AbstractVerticle {
    TcpEventBusBridge bridge;
    int port = 8086;

    @Override
    public void start(Future startFuture) throws Exception {
        vertx.eventBus().consumer("echo", message -> {
            System.out.println("Server received->" + message.body());
            message.reply(message.body());
        });

        BridgeOptions options = new BridgeOptions()
                .addInboundPermitted(new PermittedOptions().setAddress("echo"))
                .addOutboundPermitted(new PermittedOptions().setAddress("echo"));
        bridge = TcpEventBusBridge.create(vertx, options);
        bridge.listen(port, result -> {
           if (result.succeeded()) {
               System.out.println("Bridge started at port " + port);
           } else {
               System.out.println("Bridge failed");
               result.cause().printStackTrace();
           }
        });
        startFuture.complete();
    }

    @Override
    public void stop() throws Exception {
        bridge.close();
    }
}

4. TcpClientVerticle

package io.example.tcp;

import io.vertx.core.AbstractVerticle;
import io.vertx.core.Future;
import io.vertx.core.json.JsonObject;
import io.vertx.core.net.NetClient;
import io.vertx.core.net.NetSocket;
import io.vertx.ext.eventbus.bridge.tcp.impl.protocol.FrameHelper;
import io.vertx.ext.eventbus.bridge.tcp.impl.protocol.FrameParser;

public class TcpClientVerticle extends AbstractVerticle {
    NetSocket netSocket;

    @Override
    public void start(Future startFuture) throws Exception {
        NetClient client = vertx.createNetClient();
        client.connect(8086, "127.0.0.1", result -> {
            if (result.succeeded()) {
                System.out.println("NetClient连接成功");
                netSocket = result.result();
                vertx.setPeriodic(1000L, l ->
                   FrameHelper.sendFrame("send",
                           "echo",
                           "echo",
                           new JsonObject().put("hello", "world"),
                           netSocket)
                );

                netSocket.handler(new FrameParser(bufferResult -> {
                    if (bufferResult.succeeded()) {
                        JsonObject resultObj = bufferResult.result();
                        System.out.println("解析Buffer成功->" + resultObj.toString());
                    } else {
                        System.out.println("解析Buffer失败");
                    }
                }));
            } else {
                System.out.println("NetClient连接失败");
                result.cause().printStackTrace();
            }
        });
        startFuture.complete();
    }

    @Override
    public void stop() throws Exception {
        netSocket.close();
    }
}

在改写完这个例子后突然想到一个问题：既然是直接处理 TCP 且文档中给出了协议的格式，那直接使用 Java 的 TCP 即可与Vert.x-tcp-eventbus-bridge 进行通信了。所以又写了个 TCP 直接与 Vert.x-tcp-eventbus-bridge 通信的示例代码。如果项目中不想依赖 Vert.x 相关的 jar 包，下面示例代码中的 JsonObject 可替换为其他 json 库的 JSONObject。

package io.example.tcp;

import com.google.common.primitives.Bytes;
import com.google.common.primitives.Ints;
import io.vertx.core.json.JsonObject;

import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
import java.nio.charset.StandardCharsets;
import java.text.SimpleDateFormat;
import java.util.Date;

public class TcpClient {
    public static void main(String[] args) throws Exception {
        Socket socket = new Socket("127.0.0.1", 8086);
        OutputStream out = socket.getOutputStream();
        String time = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date());
        String requestJsonStr = new JsonObject()
                .put("type", "send")
                .put("address", "echo")
                .put("replyAddress", "echo")
                .put("body", new JsonObject().put("time", "Now is " + time))
                .toString();
        byte[] requestJsonBytes = requestJsonStr.getBytes(StandardCharsets.UTF_8);
        byte[] lengthBytes = Ints.toByteArray(requestJsonBytes.length);
        // Frame字节数组
        byte[] frameBytes = Bytes.concat(lengthBytes, requestJsonBytes);
        out.write(frameBytes);
        out.flush();
        System.out.println("发送信息完成->" + requestJsonStr);

        byte[] bytes = new byte[1024];
        InputStream in = socket.getInputStream();
        int len = in.read(bytes);
        String responseStr = new String(bytes, 4, len - 4);
        System.out.println("Response->" + responseStr);

        out.close();
        in.close();
        socket.close();
    }
}