JMS 1.1 五大訊息類型完整指南：建立、發送與解碼實戰

JMS 1.1 規範五種訊息類型

1. TextMessage - 文字訊息
2. BytesMessage - 位元組陣列訊息
3. MapMessage - 名值對映射訊息
4. StreamMessage - 原始型別串流訊息
5. ObjectMessage - 序列化物件訊息

1. TextMessage：股票報價字串

建立與發送

String stockData = "..."; // 股票資訊字串
TextMessage message = session.createTextMessage();
message.setText(stockData);
producer.send(message);

接收與解碼

String stockInfo = message.getText();

2. BytesMessage：二進制格式股票報價

建立與發送

byte[] stockData = ...; // 伺服器知曉編碼、客戶端知曉解碼
BytesMessage message = session.createBytesMessage();
message.writeBytes(stockData);
producer.send(message);

接收與解碼

byte[] stockInfo = new byte[1024];
int length = message.readBytes(stockInfo);
// 客戶端依協定解析 byte 陣列

3. MapMessage：多欄位名值對（如股票明細）

建立與發送

MapMessage message = session.createMapMessage();
message.setString("Name", "CN-Java");
message.setDouble("Value", stockValue);
message.setLong("Time", stockTime);
message.setDouble("Diff", stockDiff);
message.setString("Info", "Recent server announcement causes market interest");
producer.send(message);

接收與解碼

String stockName = message.getString("Name");
double stockValue = message.getDouble("Value");
long stockTime = message.getLong("Time");
double stockDiff = message.getDouble("Diff");
String stockInfo = message.getString("Info");
// 取得所有鍵名：message.getMapNames()

4. StreamMessage：依序寫入/讀取原始型別

建立與發送

StreamMessage message = session.createStreamMessage();
message.writeString(stockName);
message.writeDouble(stockValue);
message.writeLong(stockTime);
message.writeDouble(stockDiff);
message.writeString(stockInfo);
producer.send(message);

接收與解碼（須依相同順序）

String stockName = message.readString();
double stockValue = message.readDouble();
long stockTime = message.readLong();
double stockDiff = message.readDouble();
String stockInfo = message.readString();

5. ObjectMessage：傳送 Java 物件

建立與發送

StockObject stockObject = new StockObject();
stockObject.setName(stockName);
stockObject.setValue(stockValue);
stockObject.setTime(stockTime);
stockObject.setDiff(stockDiff);
stockObject.setInfo(stockInfo);

ObjectMessage message = session.createObjectMessage();
message.setObject(stockObject);
producer.send(message);

接收與解碼

StockObject stockObject = (StockObject) message.getObject();
String stockName = stockObject.getName();
double stockValue = stockObject.getValue();
long stockTime = stockObject.getTime();
double stockDiff = stockObject.getDiff();
String stockInfo = stockObject.getInfo();

注意：接收端需有相同類別定義，且類別必須實作 Serializable。

選型建議