rabbitmq管理頁面發送消息

Delivery mode: 是否持久化，1 - Non-persistent，2 - Persistent
Headers：Headers can have any name. Only long string headers can be set here.

__TypeId__: 消息體實體類類型 當需要在消費端對應實體類接受時 
需要設置該屬性 值為對應實體類在項目下的全路徑 ${包名.類名}
不加這個也可以

1. Properties: You can set other message properties here
   (delivery mode and headers are pulled out as the most common cases). Invalid properties will be ignored. Valid properties are:
   content_type ： 消息內容的類型 text/json application/json
   content_encoding： 消息內容的編碼格式 utf-8
   priority： 消息的優先級
   correlation_id：關聯id
   reply_to：用於指定回復的隊列的名稱
   expiration： 消息的失效時間
   message_id： 消息id
   timestamp：消息的時間戳
   type：類型
   user_id：用戶id
   app_id：應用程序id
   cluster_id: 集群id

2. Payload: 消息內容(必須是以字符串形式傳入)

   demo：content_type application/json
   

`MQ消費端轉換報錯：
主要錯誤信息：

Caused by: org.springframework.messaging.converter.MessageConversionException: Cannot convert from [[B] to [com.***.***.***.***] for GenericMessage 
[payload=byte[12], headers={amqp_receivedDeliveryMode=NON_PERSISTENT, amqp_receivedRoutingKey=ENT_***_NOTICE, amqp_deliveryTag=4, amqp_consumerQueue=ENT_***_NOTICE,
 amqp_redelivered=false, id=cf822382-2a6e-8030-add4-b59bfa561e34, amqp_consumerTag=amq.ctag-2BJwxJlkUYKxiAkxPc67kA, timestamp=1559721028305}]

解決方法替換點mq默認的序列化器(Application中加入)。

/
**
* {@link org.springframework.boot.autoconfigure.amqp.RabbitAutoConfiguration}
*  會自動識別
* @param objectMapper json序列化實現類
* @return mq 消息序列化工具
*/
@Bean 
public MessageConverter jsonMessageConverter(ObjectMapper objectMapper) {
return new Jackson2JsonMessageConverter(objectMapper);
}
//或者
@Bean
    public MessageConverter jsonMessageConverter() {
        return new Jackson2JsonMessageConverter();
    }`

如果出現異常

` no suitable constructor found, can not deserialize from Object value (missing default constructor or creator, or perhaps need to add/enable type information?`
被序列化的實體類要有顯式使用默認無參構造方法；

import lombok.Data;

import java.io.Serializable;

/**
 * @Author: SimonHu
 * @Date: 2020/9/27 13:39
 * @Description:
 */
@Data
public class ActiveOrder implements Serializable {
    /***RabbitMQ 管理頁面手動推送消息**/
    /***
     * Publish message
     *     Properties: content_type =  application/json
     *     Payload  {"orderNo":"20200261400027361027","status":0}
     *
     *      JsonUtils.toJsonNf(new ActiveOrder("20200261400027321021"));
     */
    private static final long serialVersionUID = -5921741921463757174L;
    private String orderNo;
    private int status;
    private String key;
    
    /**
     * MessageConverter
     * json轉換需要默認無參構造方法
     **/
    public ActiveOrder() {
    }
    
    public ActiveOrder(String orderNo) {
        this.orderNo = orderNo;
    }
    
    public ActiveOrder(String orderNo, int status, String key) {
        this.orderNo = orderNo;
        this.status = status;
        this.key = key;
    }
    
    @Override
    public String toString() {
        return "ActiveOrder{" +
                "orderNo='" + orderNo + '\'' +
                ", status=" + status +
                ", key='" + key + '\'' +
                '}';
    }
}

生產者發送消息要指定content_type
RabbitMQ控制台發送Json消息

    public void sendQueneMsg(String queueName, ActiveOrder activeOrder) {
        rabbitTemplate.setQueue(queueName);
        // 生產者發送消息的時候需要設置消息id
        rabbitTemplate.setMandatory(true);
        String json = JsonUtils.toJsonNf(activeOrder);
        Message message = MessageBuilder.withBody(json.getBytes())
                .setContentType(MessageProperties.CONTENT_TYPE_JSON).setContentEncoding("utf-8")
                .setMessageId(UUID.randomUUID() + "").build();
        log.info(queueName+"=======activeOrder:=========="+json);
        log.info(queueName+"========message:========="+message.toString());
        rabbitTemplate.convertAndSend(queueName, message);
    }```