3.5. JMS MapMessage Types
Qpid supports the Java JMS
MapMessage
interface, which provides support for maps in messages. The following code shows how to send a MapMessage
in Java JMS.
Example 3.5. Sending a Java JMS MapMessage
import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import javax.jms.Connection; import javax.jms.Destination; import javax.jms.MapMessage; import javax.jms.MessageProducer; import javax.jms.Session; import java.util.Arrays; // !!! SNIP !!! MessageProducer producer = session.createProducer(queue); MapMessage m = session.createMapMessage(); m.setIntProperty("Id", 987654321); m.setStringProperty("name", "Widget"); m.setDoubleProperty("price", 0.99); List<String> colors = new ArrayList<String>(); colors.add("red"); colors.add("green"); colors.add("white"); m.setObject("colours", colors); Map<String,Double> dimensions = new HashMap<String,Double>(); dimensions.put("length",10.2); dimensions.put("width",5.1); dimensions.put("depth",2.0); m.setObject("dimensions",dimensions); List<List<Integer>> parts = new ArrayList<List<Integer>>(); parts.add(Arrays.asList(new Integer[] {1,2,5})); parts.add(Arrays.asList(new Integer[] {8,2,5})); m.setObject("parts", parts); Map<String,Object> specs = new HashMap<String,Object>(); specs.put("colours", colors); specs.put("dimensions", dimensions); specs.put("parts", parts); m.setObject("specs",specs); producer.send(m);
The following table shows the datatypes that can be sent in a
MapMessage
, and the corresponding datatypes that will be received by clients in Python or C++.
Java Datatype | Python | C++ |
---|---|---|
boolean | bool | bool |
short | int | long | int16 |
int | int | long | int32 |
long | int | long | int64 |
float | float | float |
double | float | double |
java.lang.String | unicode | std::string |
java.util.UUID | uuid | qpid::types::Uuid |
java.util.Map[a] | dict | Variant::Map |
java.util.List | list | Variant::List |
[a]
In Qpid, maps can nest. This goes beyond the functionality required by the JMS specification.
|