The Scheduler API and WASScheduler MBean API support different
implementations of the TaskInfo interface, each of which can be used to schedule
a particular type of work. This topic describes how to create a task that
sends a Java Message Service (JMS) message to a queue or topic.
About this task
To create a task that sends a Java Message Service (JMS) message to a
queue or topic, use these steps.
Procedure
- Create an instance of the MessageTaskInfo interface using the Scheduler.createTaskInfo()
factory method. Using a JavaServer Pages (JSP) file, servlet or
EJB container, create the instance as shown in the following code example:
//lookup the scheduler to be used
Scheduler scheduler = (Scheduler)new InitialContext.lookup("java:comp/env/Scheduler");
MessageTaskInfo taskInfo = (MessageTaskInfo) scheduler.createTaskInfo(MessageTaskInfo.class);
You can also use the wsadmin tool, create the instance
as shown in the following JACL scripting example:# Sample create a task using MessageTaskInfo task type
# Call this mbean with the following parameters:
# <scheduler jndiName> = JNDI name of the scheduler resource,
# for example scheduler/myScheduler
# <JNDI name of the QCF> = The global JNDI name of the Queue Connection Factory.
# <JNDI name of the Queue> = The global JNDI name of the Queue destination
set jndiName [lindex $argv 0]
set jndiName_QCF [lindex $argv 1]
set jndiName_Q [lindex $argv 2]
# Map the JNDI name to the mbean name. The mbean name is formed by replacing the / in the jndi name
# with . and prepending Scheduler_
regsub -all {/} $jndiName "." jndiName
set mbeanName Scheduler_$jndiName
puts "Looking-up Scheduler MBean $mbeanName"
set sched [$AdminControl queryNames WebSphere®:*,type=WASScheduler,name=$mbeanName]
puts $sched
# Get the ObjectName format of the Scheduler MBean
set schedO [$AdminControl makeObjectName $sched]
# Create a MessageTaskInfo object using invoke_jmx
puts "Creating MessageTaskInfo"
set params [java::new {java.lang.Object[]} 1]
$params set 0 [java::field com.ibm.websphere.scheduler.MessageTaskInfo class]
set sigs [java::new {java.lang.String[]} 1]
$sigs set 0 java.lang.Class
set ti [$AdminControl invoke_jmx $schedO createTaskInfo $params $sigs]
set mti [java::cast com.ibm.websphere.scheduler.MessageTaskInfo $ti]
puts "Created the MessageTaskInfo object: $mti"
Attention: Creating a MessageTaskInfo object does not add
the task to the persistent store. Rather, it creates a placeholder for the
necessary data. The task is not added to the persistent store until the create()
method is called on a Scheduler, as described in the Submitting a task to
a scheduler topic.
- Set parameters on the MessageTaskInfo object. The TaskInfo
interface contains various set() methods that can be used to control execution
of the task, including when the task runs and what work the task does when
it starts.
The TaskInfo interface specifies additional behavior settings,
as documented in the API documentation. Using a JavaServer Pages (JSP) file,
servlet or EJB container, create the instance as shown in the following code
example:
//create a date object which represents 30 seconds from now
java.util.Date startDate = new java.util.Date(System.currentTimeMillis()+30000);
//now set the start time and the JNDI names for the queue connection factory and the queue
taskInfo.setConnectionFactoryJndiName("jms/MyQueueConnectionFactory");
taskInfo.setDestination("jms/MyQueue");
taskInfo.setStartTime(startDate);
You can also use the wsadmin
tool, to create the instance as shown in the following JACL scripting example:# Setup the task
puts "Setting up the task..."
# Set the startTime if you want the task to run at a specific time, for example:
$mti setStartTime [java::new {java.util.Date long} [java::call System currentTimeMillis]]
# Set the StartTimeInterval so the task runs in 30 seconds from now
$mti setStartTimeInterval 30seconds
# Set the global JNDI name of the QCF & Queue to send the message to.
$mti setConnectionFactoryJndiName $jndiName_QCF
$mti setDestinationJndiName $jndiName_Q
# Set the message
$mti setMessageData "Test Message"
# Do not purge the task when it's complete
$mti setAutoPurge false
# Set the name of the task. This can be any string value.
$mti setName Created_by_MBean
# If the task needs to run with specific authorization you can set the tasks Authentication Alias
# Authentication aliases are created using the Admin Console.
# $mti setAuthenticationAlias {myRealm/myAlias}
puts "Task setup completed."
Results
A MessageTaskInfo object has been created that contains all of the
relevant data for a task that sends a JMS message.
What to do next
Submit the task to a scheduler for creation, as described in the
Submitting a task to a scheduler topic.