(二) RabbitMQ實戰教程(面向Java開發人員)之Rabbit Java Client__Java

RabbitMQ Java Client

在介紹完RabbitMQ基本概念後，我們使用JAVA代碼來類比一套生產者和消費者的模型，Talk is cheap 直接上代碼了。使用Java Client整合RabbitMQ需要在pom.xml中匯入如下依賴

<dependency>    <groupId>com.rabbitmq</groupId>    <artifactId>amqp-client</artifactId>    <version>5.0.0</version></dependency>

本系列部落格源碼GIT地址:https://github.com/RobertoHuang/RGP-RABBITMQ.git 相關代碼

1.建立串連工具類

public class ChannelUtils {    public static Channel getChannelInstance(String connectionDescription) {        try {            ConnectionFactory connectionFactory = getConnectionFactory();            Connection connection = connectionFactory.newConnection(connectionDescription);            return connection.createChannel();        } catch (Exception e) {            throw new RuntimeException("擷取Channel串連失敗");        }    }    private static ConnectionFactory getConnectionFactory() {        ConnectionFactory connectionFactory = new ConnectionFactory();        // 配置串連資訊        connectionFactory.setHost("192.168.56.128");        connectionFactory.setPort(5672);        connectionFactory.setVirtualHost("/");        connectionFactory.setUsername("roberto");        connectionFactory.setPassword("roberto");        // 網路異常自動連接恢複        connectionFactory.setAutomaticRecoveryEnabled(true);        // 每10秒嘗試重試串連一次        connectionFactory.setNetworkRecoveryInterval(10000);        // 設定ConnectionFactory屬性資訊        Map<String, Object> connectionFactoryPropertiesMap = new HashMap();        connectionFactoryPropertiesMap.put("principal", "RobertoHuang");        connectionFactoryPropertiesMap.put("description", "RGP訂單系統V2.0");        connectionFactoryPropertiesMap.put("emailAddress", "RobertoHuang@foxmail.com");        connectionFactory.setClientProperties(connectionFactoryPropertiesMap);        return connectionFactory;    }}

2.建立訊息生產者

public class MessageProducer {    public static void main(String[] args) throws IOException, TimeoutException {        Channel channel = ChannelUtils.getChannelInstance("RGP訂單系統訊息生產者");        // 聲明交換器 (交換器名, 交換器類型, 是否持久化, 是否自動刪除, 是否是內部交換器, 交換器屬性);        channel.exchangeDeclare("roberto.order", BuiltinExchangeType.DIRECT, true, false, false, new HashMap<>());        // 設定訊息屬性 發布訊息 (交換器名, Routing key, 可靠訊息相關屬性 後續會介紹, 訊息屬性, 訊息體);        AMQP.BasicProperties basicProperties = new AMQP.BasicProperties().builder().deliveryMode(2).contentType("UTF-8").build();        channel.basicPublish("roberto.order", "add", false, basicProperties, "訂單資訊".getBytes());    }}

3.建立訊息消費者

public class MessageConsumer {    public static void main(String[] args) throws IOException, TimeoutException {        Channel channel = ChannelUtils.getChannelInstance("RGP訂單系統訊息消費者");        // 聲明隊列 (隊列名, 是否持久化, 是否排他, 是否自動刪除, 隊列屬性);        AMQP.Queue.DeclareOk declareOk = channel.queueDeclare("roberto.order.add", true, false, false, new HashMap<>());        // 聲明交換器 (交換器名, 交換器類型, 是否持久化, 是否自動刪除, 是否是內部交換器, 交換器屬性);        channel.exchangeDeclare("roberto.order", BuiltinExchangeType.DIRECT, true, false, false, new HashMap<>());        // 將隊列Binding到交換器上 (隊列名, 交換器名, Routing key, 綁定屬性);        channel.queueBind(declareOk.getQueue(), "roberto.order", "add", new HashMap<>());        // 消費者訂閱訊息 監聽如上聲明的隊列 (隊列名, 是否自動應答(與訊息可靠有關 後續會介紹), 消費者標籤, 消費者)        channel.basicConsume(declareOk.getQueue(), true, "RGP訂單系統ADD處理邏輯消費者", new DefaultConsumer(channel) {            @Override            public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {                System.out.println(consumerTag);                System.out.println(envelope.toString());                System.out.println(properties.toString());                System.out.println("訊息內容:" + new String(body));            }        });    }}

4.依次啟動訊息消費者和訊息生產者，控制台列印

RGP訂單系統ADD處理邏輯消費者Envelope(deliveryTag=1, redeliver=false, exchange=roberto.order, routingKey=add)#contentHeader<basic>(content-type=UTF-8, content-encoding=null, headers=null, delivery-mode=2, priority=null, correlation-id=null, reply-to=null, expiration=null, message-id=null, timestamp=null, type=null, user-id=null, app-id=null, cluster-id=null)訊息內容:訂單資訊

注意:初次運行時一定要先運行消費者後運行生產者，因為初次運行時還沒有聲明隊列和交換器的綁定關係，如果先啟動生產者會導致訊息無法被正確路由而被丟棄 控制台配置

運行上訴代碼後，開啟RabbitMQ管理主控台介面看到配置如下
串連屬性配置:

交換器屬性配置:

隊列屬性配置:

將管理主控台屬性與上訴代碼結合起來會更有利於讀者理解每行代碼的實際意義