How do I use persistence?

Submitted by: Administrator
Use the following guidelines:
1. Make sure the JMSServer you are using has a store configured. The JMSServer configuration entry in the config.xml file should contain a line of the form

Store="<YOUR-STORE-NAME>"

Note that if JMS boots without a store configured, it is assumed the customer did not want one, and persistent messages are silently downgraded to non-persistent (as specified for JMS 1.0.2).

2. Make sure you are not using "Message.setJMSDeliveryMode". This is overwritten, as it is a vendor-only method.

3. Make sure you are calling either:

QueueSender.send(msg, deliveryMode, ...)

-- or --

QueueSender.setDeliveryMode(deliveryMode)

-- or --

set the DefaultDeliveryMode mode on connection factory in the config.xml file to persistent (the QueueSender.setDeliver/send overrides this value). Similarly, for topics, you would set this via the TopicPublisher.

4. Make sure you don't have "DeliveryModeOverride" set to Non-Persistent on the Destination in the config.xml file.

5. If you are using pub/sub, only durable subscriptions persist messages. Non-durable subscriptions have no need to persist messages, as by definition they only exist for the life of the server.

6. If you are using JDBC, the JDBC tables, JMSSTATE and JMSSTORE, are created automatically when the JMS server boots. The DDL files used to create the tables are stored in weblogic.jar in weblogic/jms/ddl. The example configuration below shows a JDBC store for Oracle (client version 8.1.7 or later is needed to run with WLS 6.1 on JDK 1.3). To manually create the tables (also deleting any existing tables), run java utils.Schema as described in the previous question.

See the question, "How do I start WLS and configure JMS?" for a description of how to configure JMS.

Here is a sample config.xml file resulting from configuring JMS. It should look similar to yours. If you want JMS to use a file store instead of a database, just change JDBCStore to FileStore in the JMSServer section.

<Server Name="myserver"
ListenPort="7001" DefaultProtocol="t3"
ThreadPoolSize="8" >
</Server>
<Security Realm="defaultRealm"
GuestDisabled="false" />
<Realm Name="defaultRealm"
FileRealm="defaultFileRealm" />
<FileRealm Name="defaultFileRealm"
/>
<JMSServer Name="TestJMSServer"
TemporaryTemplate="TestTemplate1"
Targets="myserver" Store="JDBCStore">
<JMSQueue Name="TestQueue1"
JNDIName="jms.queue.TestQueue1"
Template="TestTemplate1"
/>
</JMSServer>
<JMSTemplate Name="TestTemplate1"
/>
<JMSFileStore Name="FileStore"
Directory="myfilestore"
JMSServer="TestJMSServer"
/>
<JMSJDBCStore Name="JDBCStore"
ConnectionPool="testpool2"
JMSServer="TestJMSServer"
/>
<JDBCConnectionPool Name="testpool2"
Targets="myserver"
URL="jdbc:weblogic:oracle"
DriverName="weblogic.jdbc.oci.Driver"
InitialCapacity="0"
MaxCapacity="1"
CapacityIncrement="1"
Properties="user=SCOTT;password=tiger;server=bay816"
/>
</Domain>

The following is a sample class that sends
a Topic message on construction:

import javax.naming.*;
import javax.jms.*;
import java.util.Hashtable;

public class t

{
public final static String DESTINATION="jms.topic.TestTopic1";

private TopicConnectionFactory connectionFactory;
private TopicConnection connection;
private TopicSession session;
private TopicPublisher producer;
private TextMessage message;
private Topic destination;

public t()
{
try {
Hashtable env = new Hashtable();
env.put(Context.INITIAL_CONTEXT_FACTORY,
"weblogic.jndi.WLInitialContextFactory");
env.put(Context.PROVIDER_URL, "t3://localhost:7001");
InitialContext ctx = new InitialContext(env);
destination = (Topic) ctx.lookup(DESTINATION);
connectionFactory = (TopicConnectionFactory)
ctx.lookup("javax.jms.TopicConnectionFactory");
connection = (TopicConnection)
connectionFactory.createTopicConnection();
session = (TopicSession) connection.createTopicSession(false,
Session.AUTO_ACKNOWLEDGE);
producer = (TopicPublisher) session.createPublisher(destination);
producer.setDeliveryMode(DeliveryMode.PERSISTENT);
message = (TextMessage) session.createTextMessage();
message.setText("hello world");
producer.publish(message);
} catch (Exception e) {
}
}
}
Submitted by: Administrator

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