42.4. Working with JMS Message Properties
Abstract
The Apache CXF JMS transport has a context mechanism that can be used to inspect a JMS message's properties. The context mechanism can also be used to set a JMS message's properties.
Getting the JMS Message Headers in a Service
To get the JMS message header properties from the
WebServiceContext
object, do the following:
- Obtain the context as described in the section called “Obtaining a context”.
- Get the message headers from the message context using the message context's
get()
method with the parameterorg.apache.cxf.transports.jms.JMSConstants.JMS_SERVER_HEADERS
.
Example 42.12, “Getting JMS Message Headers in a Service Implementation” shows code for getting the JMS message headers from a service's message context:
Example 42.12. Getting JMS Message Headers in a Service Implementation
import org.apache.cxf.transport.jms.JMSConstants; import org.apache.cxf.transports.jms.context.JMSMessageHeadersType; @WebService(serviceName = "HelloWorldService", portName = "HelloWorldPort", endpointInterface = "org.apache.cxf.hello_world_jms.HelloWorldPortType", targetNamespace = "http://cxf.apache.org/hello_world_jms") public class GreeterImplTwoWayJMS implements HelloWorldPortType { @Resource protected WebServiceContext wsContext; ... @WebMethod public String greetMe(String me) { MessageContext mc = wsContext.getMessageContext(); JMSMessageHeadersType headers = (JMSMessageHeadersType) mc.get(JMSConstants.JMS_SERVER_HEADERS); ... } ... }
Getting JMS Message Header Properties in a Consumer
Once a message is successfully retrieved from the JMS transport you can inspect the JMS header properties using the consumer's response context. In addition, you can set or check the length of time the client will wait for a response before timing out, as described in the section called “Client Receive Timeout”.
To get the JMS message headers from a consumer's response context do the following:
- Get the response context as described in the section called “Obtaining a context”.
- Get the JMS message header properties from the response context using the context's
get()
method withorg.apache.cxf.transports.jms.JMSConstants.JMS_CLIENT_RESPONSE_HEADERS
as the parameter.
Example 42.13, “Getting the JMS Headers from a Consumer Response Header” shows code for getting the JMS message header properties from a consumer's response context.
Example 42.13. Getting the JMS Headers from a Consumer Response Header
import org.apache.cxf.transports.jms.context.*; // Proxy greeter initialized previously 1BindingProvider bp = (BindingProvider)greeter; 2Map<String, Object> responseContext = bp.getResponseContext(); 3JMSMessageHeadersType responseHdr = (JMSMessageHeadersType) responseContext.get(JMSConstants.JMS_CLIENT_RESPONSE_HEADERS); ... }
The code in Example 42.13, “Getting the JMS Headers from a Consumer Response Header” does the following:
42.4.2. Inspecting the Message Header Properties
Standard JMS Header Properties
Table 42.3, “JMS Header Properties” lists the standard properties in the JMS header that you can inspect.
Property Name | Property Type | Getter Method |
---|---|---|
Correlation ID | string | getJMSCorralationID() |
Delivery Mode | int | getJMSDeliveryMode() |
Message Expiration | long | getJMSExpiration() |
Message ID | string | getJMSMessageID() |
Priority | int | getJMSPriority() |
Redelivered | boolean | getJMSRedlivered() |
Time Stamp | long | getJMSTimeStamp() |
Type | string | getJMSType() |
Time To Live | long | getTimeToLive() |
Optional Header Properties
In addition, you can inspect any optional properties stored in the JMS header using
JMSMessageHeadersType.getProperty()
. The optional properties are returned as a List
of org.apache.cxf.transports.jms.context.JMSPropertyType
. Optional properties are stored as name/value pairs.
Example
Example 42.14, “Reading the JMS Header Properties” shows code for inspecting some of the JMS properties using the response context.
Example 42.14. Reading the JMS Header Properties
// JMSMessageHeadersType messageHdr retrieved previously 1System.out.println("Correlation ID: "+messageHdr.getJMSCorrelationID()); 2System.out.println("Message Priority: "+messageHdr.getJMSPriority()); 3System.out.println("Redelivered: "+messageHdr.getRedelivered()); JMSPropertyType prop = null; 4List<JMSPropertyType> optProps = messageHdr.getProperty(); 5Iterator<JMSPropertyType> iter = optProps.iterator(); 6while (iter.hasNext()) { prop = iter.next(); System.out.println("Property name: "+prop.getName()); System.out.println("Property value: "+prop.getValue()); }
The code in Example 42.14, “Reading the JMS Header Properties” does the following:
- 1
- Prints the value of the message's correlation ID.
- 2
- Prints the value of the message's priority property.
- 3
- Prints the value of the message's redelivered property.
- 4
- Gets the list of the message's optional header properties.
- 5
- Gets an
Iterator
to traverse the list of properties. - 6
- Iterates through the list of optional properties and prints their name and value.
42.4.3. Setting JMS Properties
Abstract
Using the request context in a consumer endpoint, you can set a number of the JMS message header properties and the consumer endpoint's timeout value. These properties are valid for a single invocation. You must reset them each time you invoke an operation on the service proxy.
Note that you cannot set header properties in a service.
JMS Header Properties
Table 42.4, “Settable JMS Header Properties” lists the properties in the JMS header that can be set using the consumer endpoint's request context.
Property Name | Property Type | Setter Method |
---|---|---|
Correlation ID | string | setJMSCorralationID() |
Delivery Mode | int | setJMSDeliveryMode() |
Priority | int | setJMSPriority() |
Time To Live | long | setTimeToLive() |
- Create an
org.apache.cxf.transports.jms.context.JMSMessageHeadersType
object. - Populate the values you want to set using the appropriate setter methods described in Table 42.4, “Settable JMS Header Properties”.
- Set the values to the request context by calling the request context's
put()
method usingorg.apache.cxf.transports.jms.JMSConstants.JMS_CLIENT_REQUEST_HEADERS
as the first argument, and the newJMSMessageHeadersType
object as the second argument.
Optional JMS Header Properties
You can also set optional properties to the JMS header. Optional JMS header properties are stored in the
JMSMessageHeadersType
object that is used to set the other JMS header properties. They are stored as a List
object containing org.apache.cxf.transports.jms.context.JMSPropertyType
objects. To add optional properties to the JMS header do the following:
- Create a
JMSPropertyType
object. - Set the property's name field using
setName()
. - Set the property's value field using
setValue()
. - Add the property to the JMS message header using
JMSMessageHeadersType.getProperty().add(JMSPropertyType)
. - Repeat the procedure until all of the properties have been added to the message header.
Client Receive Timeout
In addition to the JMS header properties, you can set the amount of time a consumer endpoint waits for a response before timing out. You set the value by calling the request context's
put()
method with org.apache.cxf.transports.jms.JMSConstants.JMS_CLIENT_RECEIVE_TIMEOUT
as the first argument and a long representing the amount of time in milliseconds that you want the consumer to wait as the second argument.
Example
Example 42.15, “Setting JMS Properties using the Request Context” shows code for setting some of the JMS properties using the request context.
Example 42.15. Setting JMS Properties using the Request Context
import org.apache.cxf.transports.jms.context.*; // Proxy greeter initialized previously 1InvocationHandler handler = Proxy.getInvocationHandler(greeter); BindingProvider bp= null; 2if (handler instanceof BindingProvider) { 3 bp = (BindingProvider)handler; 4 Map<String, Object> requestContext = bp.getRequestContext(); 5 JMSMessageHeadersType requestHdr = new JMSMessageHeadersType(); 6 requestHdr.setJMSCorrelationID("WithBob"); 7 requestHdr.setJMSExpiration(3600000L); 8 JMSPropertyType prop = new JMSPropertyType; 9 prop.setName("MyProperty"); prop.setValue("Bluebird"); 10 requestHdr.getProperty().add(prop); 11 requestContext.put(JMSConstants.CLIENT_REQUEST_HEADERS, requestHdr); 12 requestContext.put(JMSConstants.CLIENT_RECEIVE_TIMEOUT, new Long(1000)); }
The code in Example 42.15, “Setting JMS Properties using the Request Context” does the following:
- 1
- Gets the
InvocationHandler
for the proxy whose JMS properties you want to change. - 2
- Checks to see if the
InvocationHandler
is aBindingProvider
. - 3
- Casts the returned
InvocationHandler
object into aBindingProvider
object to retrieve the request context. - 4
- Gets the request context.
- 5
- Creates a
JMSMessageHeadersType
object to hold the new message header values. - 6
- Sets the Correlation ID.
- 7
- Sets the Expiration property to 60 minutes.
- 8
- Creates a new
JMSPropertyType
object. - 9
- Sets the values for the optional property.
- 10
- Adds the optional property to the message header.
- 11
- Sets the JMS message header values into the request context.
- 12
- Sets the client receive timeout property to 1 second.