Usage Notes

This section provides information related to using the JMS Listener resource adapter, which is organized into the following sections:

• Connections

• Message Mapping

• Guaranteed Delivery/Reliable Processing

• LifeCycle Listener

• Reconnections

• JMX Monitoring

Connections

When Active Sync processing begins, a connection to the source messaging system is first made using the connection factory specified with the JNDI name of Connection factory resource parameter field. If specified, the User and Password fields are used for authentication when establishing the connection. If the fields are not specified, the connection are established using the default authentication.

The JMS Listener adapter operates in synchronous mode. It establishes a synchronous message consumer on the queue or topic destination specified by the JNDI name of Destination field. During each poll interval, the adapter will receive and process all available messages. Messages can be (optionally) additionally qualified by defining a valid JMS message selector string for the Message Selector field.

The connection factory and destination attributes must specify objects that correspond to the specified destination type. If a destination type of Durable Topic is specified, the additional fields of Durable Topic ClientID and Durable Topic Subscription Label are used to configure the durable subscription.

Message Mapping

When the adapter processes a qualified message, the received JMS message is first converted to a map of named values using the mechanism specified by the Message Mapping field. Refer to this resulting map as the message value map.

The message value map is then translated to the Active Sync map using the account attributes schema map. If the adapter has account attributes specified, the adapter searches the message value map for key names that also appear as a resource user attribute in the schema map. If present, the value is copied to the Active Sync map, but the entry name in the Active Sync map is translated to the name specified in the Identity system user attribute column in the schema map.

If the message value map has an entry that cannot be translated using the account attributes schema map, then the entry from the message value map is copied unaltered to the Active Sync map.

Guaranteed Delivery/Reliable Processing

The responsibility of guaranteed delivery lies with the sender of the message. Only messages sent persistently will be stored until delivered by the messaging system. This guarantees that the message will not be lost due to a crash or shutdown of the messaging system. This is referred to as once-and-only-once delivery.

The Reliable Messaging Support field indicates the form of reliable message processing the adapter should perform.

• If set to LOCAL, then the JMS session for the adapter is transacted. The session is always committed after the message is processed, regardless of any errors encountered during the processing stages. This ensures that the message is processed only once.

• If set to AUTO, then the session is not transacted, but the message is automatically acknowledged immediately according to the JMS definition of AUTO_ACK.

• If set to DUPS_OK, then the session is not transacted, but the message is automatically acknowledged immediately according to the JMS definition of DUPS_OK_ACK.

• If set to CLIENT, then the session is not transacted, and the message is not acknowledged by the adapter. Instead, it is expected that a lifecycle listener specified by the Message LifeCycle Listener field acknowledges the message as needed. The lifecycle listener is called with an AWAITING_CLIENT_ACK lifecycle event at the typical point that an acknowledgement is expected. It is rare that this mode is needed.

LifeCycle Listener

An optional lifecycle listener class can be registered with the adapter with the Message LifeCycle Listener field. The lifecycle listener can be used to perform:

• Custom logging of the processing stages of the adapter

• Custom manipulation of data during processing stages of the adapter

• Custom acknowledgement of messages received with CLIENT_ACK mode

Reconnections

If connection is lost to the messaging system (for example, the messaging system server has been shut down), the adapter can be configured to periodically attempt to reconnect with the messaging system to re-establish the listener.

The Re-initialize upon exception check box enables reconnect behavior. You can set the frequency to attempt reconnect with the Connection Retry Frequency (secs) field.

JMX Monitoring

The JMS Listener adapter provides multiple attributes and operations that can be monitored with Java Management Extensions (JMX). For detailed information about configuring JMX on an Waveset server, refer to the Configuration chapter in Business Administrator's Guide.

On the server running the Active Sync process, (which also contains the authoritative mbean), statistics are computed based on a specified window of time. The setWindowMillis operation sets the duration of the window. Each time the statistics are computed, the actual duration of the statistics window is recorded as the ActualWindowTime attribute.

For example, the setWindowMillis operation could be set to 10000 (10 seconds), but the ActualWindowTime could contain a value of 10005, indicating the actual window was 10.005 seconds. Other attributes, such as MsgCountInWindow, use the actual window to measure or count statistics. If MsgCountInWindow contained a value of 63, then 63 messages were retrieved from JMS in 10.005 seconds.

The following tables list the attributes and operations the adapter makes available to JMX. The attributes and operations can be viewed from the JMX console under IDM/Cluster/ Synchronization/Active Sync/JMS Listener/SyncStats:DestinationName. The value for DestinationName is generated by concatenating the values of the Destination Type and JNDI name of Destination resource parameters.

JMX Attributes

JMX Operations