The connector for WebSphere MQ can recognize and read two kinds of meta-objects:
The attribute values of the dynamic child meta-object duplicate and override those of the static meta-object.
The WebSphere MQ static meta-object consists of a list of conversion properties defined for different business objects. To define the conversion properties for a business object, first create a string attribute and name it using the syntax busObj_verb. For example, to define the conversion properties for a Customer object with the verb Create, create an attribute named Customer_Create. In the application-specific text of the attribute, you specify the actual conversion properties.
The table below describes the meta-object properties.
Property name | Description |
---|---|
CorrelationID | This property affects adapter behavior during request processing only and is handled the same as the CorrelationID property in the dynamic meta-object. For more information, see Asynchronous request processing. |
CollaborationName | The
CollaborationName must be specified in the application
specific text of the attribute for the business object/verb
combination. For example, if a user expects to handle synchronous
requests for the business object Customer with the Create verb, the
static metadata object must contain an attribute named
Customer_Create.
The Customer_Create attribute must contain application specific text that includes a name-value pair. For example, CollaborationName=MyCustomerProcessingCollab. See the Application-specific information section for syntax details. Failure to do this will result in run-time errors when the connector attempts to synchronously process a request involving the Customer business object.
|
DataEncoding |
DataEncoding is the encoding to be used to read and write messages. If this property is not specified in the static meta-object, the connector tries to read the messages without using any specific encoding. DataEncoding defined in a dynamic child meta-object overrides the value defined in the static meta-object. The default value is Text. The format for the value of this attribute is messageType[:enc]. I.e., Text:ISO8859_1, Text:UnicodeLittle, Text, or Binary.This property is related internally to the InputFormat property: specify one and only one DataEncoding per InputFormat. |
DataHandlerConfigMO | Meta-object passed to data handler to provide configuration information. If specified in the static meta-object, this will override the value specified in the DataHandlerConfigMO connector property. Use this static meta-object property when different data handlers are required for processing different business object types. If defined in a dynamic child meta-object, this property will override the connector property and the static meta-object property. Use the dynamic child meta-object for request processing when the data format may be dependent on the actual business data. The specified business object must be supported by the connector. |
DataHandlerMimeType | Allows you to request a data handler based on a particular MIME type. If specified in the static meta-object, this will override the value specified in the DataHandlerMimeType connector property. Use this static meta-object property when different data handlers are required for processing different business object types. If defined in a dynamic child meta-object, this property will override the connector property and the static meta-object property. Use the dynamic child meta-object for request processing when the data format might be dependent on the actual business data. The business object specified in DataHandlerConfigMO should have an attribute that corresponds to the value of this property. |
DoNotReportBusObj | Optionally,
the user can include the DoNotReportBusObj property. By
setting this property to true, all PAN report messages
issued will have a blank message body. This is recommended when a
requestor wants to confirm that a request has been successfully
processed and does not need notification of changes to the business
object. This does not effect NAN reports.
If this property is not found in the static meta-object, the connector will default it to false and populate the message report with the business object.
|
InputFormat |
The InputFormat is the message format to associate with the given business object. When a message is retrieved and is in this format, it is converted to the given business object if possible. This property is related internally to the DataEncoding property: Specify one and only oneDataEncoding per InputFormat. Do not set this property using default conversion properties; its value is used to match incoming messages to business objects. |
OutputFormat | The OutputFormat is set on messages created from the given business object. If the OutputFormat is not specified, the input format is used, if available. An OutputFormat defined in a dynamic child meta-object overrides the value defined in the static meta-object. |
InputQueue | The input
queue that the connector polls to detect new messages.
|
OutputQueue | The OutputQueue is the output queue to which messages derived from the given business object are delivered. An OutputQueue defined in a dynamic child meta-object overrides the value defined in the static meta-object. |
ResponseTimeout | Indicates the length of time in milliseconds to wait before timing out when waiting for a response. The connector returns SUCCESS immediately without waiting for a response if this is left undefined or with a value less than zero. A ResponseTimeout defined in a dynamic child meta-object overrides the value defined in the static meta-object. |
TimeoutFatal | If this property is defined and has a value of True, the connector returns APP_RESPONSE_TIMEOUT when a response is not received within the time specified by ResponseTimeout. All other threads waiting for response messages immediately return APP_RESPONSE_TIMEOUT to InterChange Server. This causes InterChange Server to terminate the connector. A TimeoutFatal defined in a dynamic child meta-object overrides the value defined in the static meta-object. |
Additionally, a reserved property named Default can be defined in the meta-object. When this property is present, its application-specific information specifies default values for all business object conversion properties.
Consider the following sample meta-object.
Property name | Application-specific text |
---|---|
Default |
DataEncoding=Text:UnicodeLittle; OutputFormat=CUST_OUT; OutputQueue=QueueA;ResponseTimeout=10000; TimeoutFatal=False |
The application-specific information is structured in name-value pair format, separated by semicolons. For example:
InputFormat=CUST_IN;OutputFormat=CUST_OUT
You can use the InputQueue property in the application-specific information of the static meta-object to associate a data handler with an input queue. This feature is useful when dealing with multiple trading partners who have different formats and conversion requirements. To do so you must:
For example, the following attribute in a static meta-object associates a data handler with an InputQueue named CompReceipts:
[Attribute] Name = Cust_Create Type = String Cardinality = 1 MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false AppSpecificInfo = InputQueue=//queue.manager/CompReceipts;DataHandlerClassName= com.crossworlds.DataHandlers.MQ.disposition_notification;DataHandlerMimeType= message/ disposition_notification IsRequiredServerBound = false [End]
When retrieving a message, the connector normally matches the input format to one specific business object and verb combination. The connector then passes the business object name and the contents of the message to the data handler. This allows the data handler to verify that the message contents correspond to the business object that the user expects.
If, however, the same input format is defined for more than one business object, the connector will be unable to determine which business object the data represents before passing it to the data handler. In such cases, the connector passes the message contents only to the data handler and then looks up conversion properties based on the business object that is generated. Accordingly, the data handler must determine the business object based on the message content alone.
If the verb on the generated business object is not set, the connector searches for conversion properties defined for this business object with any verb. If only one set of conversion properties is found, the connector assigns the specified verb. If more properties are found, the connector fails the message because it is unable to distinguish among the verbs.
The static meta-object shown below configures the connector to convert Customer business objects using verbs Create, Update, Delete, and Retrieve. Note that attribute Default is defined in the meta-object. The connector uses the conversion properties of this attribute:
OutputQueue=CustomerQueue1;ResponseTimeout=5000;TimeoutFatal=true
as default values for all other conversion properties. Thus, unless specified otherwise by an attribute or overridden by a dynamic child meta-object value, the connector will issue all business objects to queue CustomerQueue1 and then wait for a response message. If a response does not arrive within 5000 milliseconds, the connector terminates immediately.
Attribute Customer_Create indicates to the connector that any messages of format NEW should be converted to a Customer business object with the verb Create. Since an output format is not defined, the connector will send messages representing this object-verb combination using the format defined for input (in this case NEW).
Input format MODIFY is overloaded--defined for both business object Customer with verb Update and business object Customer with verb Delete. In order to successfully process retrieved messages of this format, the business object name and possibly the verb should be contained in the message content for the data handler to identify (see Overloading input formats). For Request processing operations, the connector will send messages for either verb using the input format MODIFY since an output format is not defined.
Attribute Customer_Retrieve specifies that business objects of type Customer with verb Retrieve should be sent as messages with format Retrieve. Note that the default response time has been overridden so that the connector will wait up 10000 milliseconds before timing out (it will still terminate if a response is not received).
[ReposCopy] Version = 3.1.0 Repositories = 1cHyILNuPTc= [End] [BusinessObjectDefinition] Name = Sample_MO Version = 1.0.0 [Attribute] Name = Default Type = String Cardinality = 1 MaxLength = 1 IsKey = true IsForeignKey = false IsRequired = false AppSpecificInfo = OutputQueue=CustomerQueue1;ResponseTimeout=5000;TimeoutFatal=true IsRequiredServerBound = false [End] [Attribute] Name = Customer_Create Type = String Cardinality = 1 MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false AppSpecificInfo = InputFormat=NEW IsRequiredServerBound = false [End] [Attribute] Name = Customer_Update Type = String Cardinality = 1 MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false AppSpecificInfo = InputFormat=MODIFY IsRequiredServerBound = false [End] [Attribute] Name = Customer_Delete Type = String Cardinality = 1 MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false AppSpecificInfo = InputFormat=MODIFY IsRequiredServerBound = false [End] [Attribute] Name = Customer_Retrieve Type = String Cardinality = 1 MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false AppSpecificInfo = OutputFormat=RETRIEVE;ResponseTimeout=10000 IsRequiredServerBound = false [End] [Attribute] Name = ObjectEventId Type = String MaxLength = 255 IsKey = false IsForeignKey = false IsRequired = false IsRequiredServerBound = false [End] [Verb] Name = Create [End] [Verb] Name = Delete [End] [Verb] Name = Retrieve [End] [Verb] Name = Update [End] [End]
If it is difficult or unfeasible to specify the necessary metadata through a static meta-object, the connector can optionally accept metadata specified at run-time for each business object instance.
The connector recognizes and reads conversion properties from a dynamic meta-object added as a child to the top-level business object passed to the connector. The attribute values of the dynamic child meta-object duplicate the conversion properties that you can specify via the static meta-object that is used to configure the connector.
Since dynamic child meta object properties override those found in static meta-objects, if you specify a dynamic child meta-object, you need not include a connector property that specifies the static meta-object. Accordingly, you can use a dynamic child meta-object independently of the static meta-object and vice-versa.
The table in the previous section and the table below show sample static and dynamic child meta-objects, respectively, for business object Customer_Create. Note that the application-specific information consists of semi-colon delimited name-value pairs.
Property name | Value |
---|---|
DataEncoding | Text:UnicodeLittle |
DataHandlerMimeType* | text/delimited |
OutputFormat | CUST_OUT |
OutputQueue | QueueA |
ResponseTimeout | 10000 |
TimeoutFatal | False |
*Assumes that DataHandlerConfigMO has been specified in either the connector configuration properties or the static meta-object.
The connector checks the application-specific information of top-level business object received to determine whether tag cw_mo_conn specifies a child meta-object. If so, the dynamic child meta-object values override those specified in the static meta-object.
In order to provide collaborations with more information regarding messages retrieved during polling, the connector populates specific attributes of the dynamic meta-object, if already defined for the business object created.
The table below shows how a dynamic child meta-object might be structured for polling.
Property name | Sample Value |
---|---|
InputFormat | CUST_IN |
InputQueue | MYInputQueue |
OutputFormat | CxIgnore |
OutputQueue | CxIgnore |
ResponseTimeout | CxIgnore |
TimeoutFatal | CxIgnore |
As shown in the table above, you can define an additional attribute, InputQueue, in a dynamic child meta-object. This attribute contains the name of the queue from which a given message has been retrieved. If this property is not defined in the child meta-object, it will not be populated.
Example scenario:
[BusinessObjectDefinition] Name = MO_Sample_Config Version = 1.0.0 [Attribute] Name = OutputFormat Type = String MaxLength = 1 IsKey = true IsForeignKey = false IsRequired = false DefaultValue = CUST IsRequiredServerBound = false [End] [Attribute] Name = OutputQueue Type = String MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false DefaultValue = OUT IsRequiredServerBound = false [End] [Attribute] Name = ResponseTimeout Type = String MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false DefaultValue = -1 IsRequiredServerBound = false [End] [Attribute] Name = TimeoutFatal Type = String MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false DefaultValue = false IsRequiredServerBound = false [End] [Attribute] Name = InputFormat Type = String MaxLength = 1 IsKey = true IsForeignKey = false IsRequired = false IsRequiredServerBound = false [End] [Attribute] Name = InputQueue Type = String MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false IsRequiredServerBound = false [End] [Attribute] Name = ObjectEventId Type = String MaxLength = 255 IsKey = false IsForeignKey = false IsRequired = false IsRequiredServerBound = false [End] [Verb] Name = Create [End] [Verb] Name = Delete [End] [Verb] Name = Retrieve [End] [Verb] Name = Update [End] [End] [BusinessObjectDefinition] Name = Customer Version = 1.0.0 AppSpecificInfo = cw_mo_conn=MyConfig [Attribute] Name = FirstName Type = String MaxLength = 1 IsKey = true IsForeignKey = false IsRequired = false IsRequiredServerBound = false [End] [Attribute] Name = LastName Type = String MaxLength = 1 IsKey = true IsForeignKey = false IsRequired = false IsRequiredServerBound = false [End] [Attribute] Name = Telephone Type = String MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false IsRequiredServerBound = false [End] [Attribute] Name = MyConfig Type = MO_Sample_Config ContainedObjectVersion = 1.0.0 Relationship = Containment Cardinality = 1 MaxLength = 1 IsKey = false IsForeignKey = false IsRequired = false IsRequiredServerBound = false [End] [Attribute] Name = ObjectEventId Type = String MaxLength = 255 IsKey = false IsForeignKey = false IsRequired = false IsRequiredServerBound = false [End] [Verb] Name = Create [End] [Verb] Name = Delete [End] [Verb] Name = Retrieve [End] [Verb] Name = Update [End] [End]
You can add attributes to a dynamic meta-object to gain more information about, and more control over, the message transport. Adding such attributes allows you to modify JMS properties, to control the ReplyToQueue on a per-request basis (rather than using the default ReplyToQueue specified in the adapter properties), and to re-target a message CorrelationID. This section describes these attributes and how they affect event notification and request processing in both synchronous and asynchronous modes.
The following attributes, which reflect JMS and WebSphere MQ header properties, are recognized in the dynamic meta-object.
Table 1. Dynamic meta-object header attributes
Header attribute name | Mode | Corresponding JMS header |
---|---|---|
CorrelationID |
Read/Write | JMSCorrelationID |
ReplyToQueue |
Read/Write | JMSReplyTo |
DeliveryMode |
Read/Write | JMSDeliveryMode |
Priority |
Read/Write | JMSPriority |
Destination |
Read | JMSDestination |
Expiration |
Read | JMSExpiration |
MessageID |
Read | JMSMessageID |
Redelivered |
Read | JMSRedelivered |
TimeStamp |
Read | JMSTimeStamp |
Type |
Read | JMSType |
UserID |
Read | JMSXUserID |
AppID |
Read | JMSXAppID |
DeliveryCount |
Read | JMSXDeliveryCount |
GroupID |
Read | JMSXGroupID |
GroupSeq |
Read | JMSXGroupSeq |
JMSProperties |
Read/Write |
Read-only attributes are read from a message header during event notification and written to the dynamic meta-object. These properties also populate the dynamic MO when a response message is issued during request processing. Read/write attributes are set on message headers created during request processing. During event notification, read/write attributes are read from message headers to populate the dynamic meta-object.
The interpretation and use of these attributes are described in the sections below.
Unlike other attributes in the dynamic meta-object, JMSProperties must define a single-cardinality child object. Every attribute in this child object must define a single property to be read/written in the variable portion of the JMS message header as follows:
The table below shows application-specific information properties that you must define for attributes in the JMSProperties object.
Table 2. Application-specific information for JMS property attributes
Name | Possible values | Comments |
---|---|---|
Name | Any valid JMS property name | This is the name of the JMS property. Some vendors reserve certain properties to provide extended functionality. In general, users should not define custom properties that begin with JMS unless they are seeking access to these vendor-specific features. |
Type | String, Int, Boolean, Float, Double, Long, Short | This is the type of the JMS property. The JMS API provides a number of methods for setting values in the JMS Message: setIntProperty, setLongProperty, setStringProperty, etc. The type of the JMS property specified here dictates which of these methods is used for setting the property value in the message. |
The figure below shows attribute JMSProperties in the dynamic meta-object and definitions for four properties in the JMS message header: ID, GID, RESPONSE and RESPONSE_PERSIST. The application-specific information of the attributes defines the name and type of each. For example, attribute ID maps to JMS property ID of type String).
Figure 3. JMS properties
attribute in a dynamic meta-object
If a dynamic meta-object with header attributes is present in the event business object, the connector performs the following steps (in addition to populating the meta-object with transport-related data):
For synchronous event processing, the adapter posts an event and waits for a response from the integration broker before sending a response message back to the application. Any changes to the business data are reflected in the response message returned. Before posting the event, the adapter populates the dynamic meta-object just as described for asynchronous event notification. The values set in the dynamic meta-object are reflected in the response-issued header as described below (all other read-only header attributes in the dynamic meta-object are ignored.):
If you do not define attribute CorrelationID in the meta-object, the connector handles the CorrelationID automatically.
The connector uses the dynamic meta-object, if present, to populate the request message prior to issuing it. The connector performs the following steps before sending a request message:
The connector uses the dynamic meta-object, if present, to populate the request message prior to issuing it. If the dynamic meta-object contains header attributes, the connector populates it with corresponding new values found in the response message. The connector performs the following steps (in addition to populating the meta-object with transport-related data) after receiving a response message:
If a JMS property cannot be read from or written to a message, the connector logs an error and the request or event fails. If a user-specified ReplyToQueue does not exist or cannot be accessed, the connector logs an error and the request fails. If a CorrelationID is invalid or cannot be set, the connector logs an error and the request fails. In all cases, the message logged is from the connector message file.