Java Message Service Resource Access From a Rich Client:
A Simple Example

We want to hear from you! Please send us your FEEDBACK. The following software tool may contain actual software programs in source code form. This source code is made available for developers to use as needed, pursuant to the terms and conditions of this license. Overview A rich client is a standalone Java platform program that can directly access Enterprise JavaBeans (EJBs) deployed on a Sun ONE Application Server. Traditionally, clients communicate with the Sun ONE Application Server through the Web tier; for example, clients using HTTP communicate with server components such as JavaServer Pages (JSPs) and Servlets which will in turn hand access to EJBs within the server context. The Java 2 Platform, Enterprise Edition (J2EE) v1.3 specification, however, requires that standalone clients be able to talk to the Sun ONE Application Server using the RMI-IIOP standard. The J2EE v1.3 specification also requires that these standalone clients operate within the Application Client Container (ACC) context. The ACC approach isolates server-specific issues, leaving clients completely portable. The Sun ONE Application Server allows Java platform clients to directly access EJBs on a Sun ONE Application Server. These clients can operate within an ACC that ships with the Sun ONE Application Server or can use a direct access approach (a non ACC path). This code sample illustrates a simple example of looking up Java Message Service (JMS) resources, and sending messages to, as well as receiving messages from a queue, via a standalone application. In the second part of the code sample, the same application is modified to work with ACC to access JMS resources . The complete sample can be downloaded from here. I.   Standalone Client Without ACC II.  Standalone Client Using ACC Standalone Client Without ACC First, we will examine a sample to look up JMS resources outside of an ACC. The sample program will send and receive the message to a queue on the Sun ONE Application Server. The sample is based on the Simple Chat Client example that is bundled with Sun ONE Application Server 7.0. Compiling and Assembling the Sample Application: The only source file that is part of this sample is SimpleQueueClient.java. This demo provides a build file build.xml that has the following target: compile-simple - This will compile the sample program. The two key points to note in the source are: 1) Since the standalone sample in this section is not a J2EE application, we are using the JMS lookup string jms/sampleQCF. 2) While creating the initialcontext object, we use: Context initialContext = new InitialContext(); We do not pass any environment properties to the InitialContext constructor as we obtain the ORB host name and port number via command line options. Deploying the Sample Application: Since this sample is a standalone example, we do not deploy it on an ACC or on the Sun ONE Application Server. Configuring Resources: The build file setup.xml has the following target that can be used to configure the JMS resources on the Application Server: run-setup-jms - Configure JMS resources to run the sample code. Modify the following Application Server installation-specific parameters in setup.xml: jmshost - Application Server hostname adminusr - Admin instance user name adminpwd - Admin instance user password adminport - Admin instance port number The run-setup-jms target will set up the following JMS-administered objects: Resource Resource Type Resource Name (Java Naming and Directory Interface) Connection Factories javax.jms.QueueConnectionFactory jms/sampleQCF Destination Resources javax.jms.Queue jms/sampleQ Running the Sample Application: This sample requires you to set the environment variable LD_LIBRARY_PATH. This variable should point to the Application Server, the Sun ONE MQ jar files and shared libraries: LD_LIBRARY_PATH=/usr/lib/mps:/opt/SUNWappserver7/lib:/usr/lib The build.xml file uses the following target to run the sample. run-client - Run the sample program to send and receive message. If the Application Server is on a different system, we need to copy all the jar files and shared libraries from the /opt/SUNWappserver7/lib, /usr/share/lib/imq and /usr/lib/mps directories to the target system. The build file build.xml will also have to be modified to point to these directories instead. The LD_LIBRARY_PATH environment variable will also change accordingly. The key points to note in the build file are the Java Virtual Machine startup options: -Dorg.omg.CORBA.ORBInitialHost=${ORBhost} -Dorg.omg.CORBA.ORBInitialPort=${ORBport} Here ORBhost is the Application Server hostname and ORBport is the ORB port number (default 3700 for server1 instance). The program output will be:      [echo] Running the Standalone JMS client program:      [echo]       [java] Looking up the initial context from JNDI :      [java] Mar 30, 2003 7:23:26 PM com.sun.enterprise.util.ORBManager initializeORBMonitoring      [java] SEVERE: UTIL6034:Could not initialize ORB monitoring      [java] java.lang.IllegalStateException: Monitorable component can not be registered because admin                service has not been initialized.      [java]     at com.iplanet.ias.admin.monitor.MonitoringHelper.registerORBMonitoringMBean(MonitoringHelper.java:305)      [java]     at com.iplanet.ias.admin.monitor.MonitoringHelper.registerSystemORBMonitoringMBean  (MonitoringHelper.java:252)      [java]     at com.sun.enterprise.util.ORBManager.initializeORBMonitoring(ORBManager.java:732)      [java]     at com.sun.enterprise.util.ORBManager.init(ORBManager.java:261)      [java]     at com.sun.enterprise.naming.SerialInitContextFactory.<init>(SerialInitContextFactory.java:31)      [java] Looking up the queue connection factory from JNDI :jms/sampleQCF      [java]     at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)      [java]     at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)      [java]     at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)      [java]     at java.lang.reflect.Constructor.newInstance(Constructor.java:274)      [java]     at java.lang.Class.newInstance0(Class.java:296)      [java]     at java.lang.Class.newInstance(Class.java:249)      [java]     at javax.naming.spi.NamingManager.getInitialContext(NamingManager.java:649)      [java]     at javax.naming.InitialContext.getDefaultInitCtx(InitialContext.java:243)      [java]     at javax.naming.InitialContext.init(InitialContext.java:219)      [java]     at javax.naming.InitialContext.<init>(InitialContext.java:175)      [java]     at samples.jms.client.SimpleQueueClient.<init>(Unknown Source)      [java]     at samples.jms.client.SimpleQueueClient.main(Unknown Source)      [java] jms/sampleQCF: com.sun.enterprise.jms.ConnectionFactoryWrapperStandalone@a68ef9      [java] Looking up the queue from JNDI      [java] jms/sampleQ: Sun ONE MQ Destination      [java] getName():          SampleQueue      [java] Class:                      com.sun.messaging.Queue      [java] getVERSION():               3.0      [java] isReadonly():               false      [java] getProperties():    {imqDestinationName=SampleQueue, imqDestinationDescription=A Description      for the Destination Object}      [java] Creating QueueConnection using the factory      [java] Starting the Connection      [java] Creating a QueueSender      [java] Creating a QueueReceiver      [java] Building a message      [java] Sending message to SampleQueue      [java] Waiting for the return message      [java]      [java] Message received: This is a sample message. It was sent at Sun Mar 30 19:23:28 PST 2003      [java] Closing QueueReceiver      [java] Closing QueueSender      [java] Closing session      [java] Closing connection    You can ignore the exception : SEVERE: UTIL6034:Could not initialize ORB monitoring java.lang.IllegalStateException: Monitorable component can not be registered because admin service has not been initialized. The logging error comes from the server's ORBManager trying to register ORBMonitoringMBean as it checks the container type, which is not an APPCLIENT_CONTAINER type in this case. Next (Standalone client using ACC)

DOC ID 1839