16 Working with Pipelines in Oracle JDeveloper

This chapter describes how to create and configure pipelines, or message flows, using Oracle JDeveloper. Sections include adding and configuring pipeline pairs, conditional branches, stages, operational branches, route nodes, and error handlers.

For more detailed information on message flows, see Modeling Message Flow in Oracle Service Bus.

This chapter includes the following sections:

• Adding a Pipeline Component in JDeveloper

• Viewing and Editing Pipelines in JDeveloper

• Adding Shared Variables to Pipelines in JDeveloper

• Adding Pipeline Pair Nodes to Pipelines in JDeveloper

• Adding Conditional Branches to Pipelines in JDeveloper

• Adding Operational Branches to Pipelines in JDeveloper

• Adding REST Branches to Pipelines in JDeveloper

• Adding Stages to Pipelines in JDeveloper

• Adding Route Nodes to Pipelines in JDeveloper

• Cutting, Copying, and Pasting Stages and Route Nodes in JDeveloper

• Configuring the Resequencer in JDeveloper

16.1 Adding a Pipeline Component in JDeveloper

Add a pipeline to define the message flow and any data transformation or validation for the project. You can also define errors and reporting in a pipeline. When you create a new pipeline, you have the option to generate a proxy service from the pipeline configuration.

16.1.1 How to Add a Pipeline in JDeveloper

You can use the Service Bus Overview Editor in Oracle JDeveloper to add a pipeline component to the service bus project.

To add a pipeline:

1. Make sure you have the Service Bus project open in Oracle JDeveloper.
2. Double-click the project icon in the Application Navigator to open the Service Bus Overview Editor. For more information about the Service Bus Overview Editor, see Introduction to the Service Bus Overview Editor.

   Note:

   You can also right-click the project folder in the Application Navigator and select New > Pipeline from the context menu that appears. Next, continue from Step 5 to configure the pipeline.

3. From the Components window, select Service Bus.
4. From the Resources list, drag a Pipeline into the Pipelines/Split Joins lane in the designer.

   The Create Pipeline Service wizard appears.

5. Configure the settings for the pipeline.

   For help with the configuration fields, click Help or press F1.

6. To generate a proxy service to associate with the pipeline, click Expose as a Proxy Service on the Type page of the wizard. Select a transport for the proxy service and, optionally, modify the name.
7. On the last page of the wizard, click Finish.

   The pipeline file is added to the project, and the pipeline appears in the Pipelines/Split Joins section of the designer. If you exposed the pipeline as a proxy service, the proxy service also appears in the Proxy Services swim lane, and the components are automatically wired.

8. To define the message flow in the pipeline, see Viewing and Editing Pipelines in JDeveloper
9. Click Save All in the JDeveloper toolbar.

16.2 Viewing and Editing Pipelines in JDeveloper

The message flow corresponding to a proxy service is handled by a pipeline. This section describes how to view and pipelines using the Pipeline Editor.

16.2.1 How to View and Edit a Pipeline in JDeveloper

Use the Pipeline Editor in Oracle JDeveloper to view and edit the message flow for the pipeline.

To view and edit a pipeline:

1. Make sure you have the Service Bus project open in Oracle JDeveloper.
2. Use one of the following methods to edit the message flow for a pipeline:

   • In Application Navigator, locate the pipeline node. Right-click the pipeline node and select Open. You can alternatively double-click the pipeline node to open it.

   • In Application Navigator, click the project node (or overview.xml) to open the Overview Editor.

     In the Overview Editor, double-click the pipeline component to open the Pipeline Editor.

   The Pipeline Editor appears. Ensure that the Design tab is selected at the bottom left corner of the editor.

   If no message flow has yet been created for the selected pipeline, the Pipeline Editor Design view shows a single icon on the page, the pipeline icon. This is the starting node for the message flow.

3. Use one of the following methods to add a pipeline component (node):

   • Right-click the start node to get options for pipeline components that you can add. Figure 16-1 shows the options available for the start node. You can add nodes like the Route node, PipelinePair node, and Conditional Branch.

     Figure 16-1 Right-Clicking a Node to Add a Pipeline Component

     
     Description of "Figure 16-1 Right-Clicking a Node to Add a Pipeline Component"

   • Alternatively, select the pipeline component to add from the Components window, and drag the component to the Pipeline Editor window. Yellow circles appear indicating valid places to drop the component in the pipeline. Drag the component to a yellow circle. The yellow circle turns green. Release the component to add it. Figure 16-2 shows a Pipeline Pair node being added to a start node.

   Figure 16-2 Adding a Pipeline Pair to the Start Node

   
   Description of "Figure 16-2 Adding a Pipeline Pair to the Start Node"

   When you add components to the editor, icons are displayed on the editor to represent the components. The relationships among the components are shown with lines and bounding boxes.

   Figure 16-3 shows a pipeline where a Pipeline Pair node has been added to the flow. The Pipeline Pair comprises of a Request Pipeline and a Response Pipeline. The Request and Response pipelines have stages that can contain action nodes.

   Figure 16-3 Pipeline with a Pipeline Pair Node

   
   Description of "Figure 16-3 Pipeline with a Pipeline Pair Node"
4. Continue to build the pipeline by adding more components to the editor. For example, to add a communication action to the stage node, you can drag the communication action from the Components window to the stage node in the editor. Alternatively, you can right-click the Stage node to get options for pipeline components that you can add to the Stage node. The options available for each component may differ, depending on context.
5. Click Save in the Oracle JDeveloper toolbar.

16.3 Adding Shared Variables to Pipelines in JDeveloper

If two pipelines in a single call chain declare the same shared variable, then they read and modify the same variable. In other words, if pipeline P1 declares a shared variable var, and pipeline P2 also declares a shared variable var, then any changes to var in P1 are visible in P2, and vice versa. A shared variable must be of the String, Boolean, or XML data type.

When a proxy service receives and processes a message, all invoked pipelines that use a shared variable, read and write the same value for the variable. A subsequent message received by the proxy creates a new instance of the shared variable in the invoked pipelines.

Shared variables work across local proxy invocations and split-join component invocations. For example, say pipelines P1 and P2 declare a shared variable. Now, if P1 invokes a local proxy service or split-join component, which in turn invokes P2, then P1 and P2 continue to share the shared variable.

The following restrictions apply to using shared variables:

• System variables (such as $body, $attachments, $operation, $inbound, $outbound) cannot be shared.

• Variables cannot be shared across non-local proxy invocations. For example, say a pipeline invokes an HTTP proxy service, the shared variable is not propagated across this call.

• Variables cannot be shared between pipeline and split-join resources.

• Variables with Java and binary content types are not supported. For example, an XML-typed variable that has <ctx:java-content/> in its XML structure, is not supported as a shared variable.

16.3.1 How to Add a Shared Variable to a Pipeline in JDeveloper

Use the Pipeline Editor to add a shared variable to the message flow for the pipeline.

To add a shared variable to a pipeline

1. In the Pipeline Editor, right-click the start node.
2. Select Add Shared Variable from the context menu that appears.
3. Enter a name for the shared variable in the Enter Shared Variable Name field.
4. Click OK to add the shared variable to the pipeline.

16.4 Adding Pipeline Pair Nodes to Pipelines in JDeveloper

Pipelines can include zero or more pipeline pair nodes: request and response pipelines for the proxy service (or for the operations on the service), and error handler pipelines that can be defined for stages, pipelines, and proxy services. Pipelines can include one or more stages, which in turn include actions.

16.4.1 How to Add a Pipeline Pair Node to a Pipeline in JDeveloper

Use the Pipeline Editor to add a pipeline pair to the message flow for the pipeline.

To add a pipeline pair to a pipeline:

1. In the Pipeline Editor, right-click the start node icon.

2. Select Insert Into > PipelinePairNode from the context menu that appears. The pipeline pair node is inserted.

   Note:

   You can alternatively choose to drag a Pipeline Pair component from the Components window to the appropriate location in the Pipeline Editor. The Pipeline Pair component can be found under the Nodes section of the Message Flow category.

3. To change the default name and add a description for the pipeline pair node, do the following:

   1. Click the Pipeline Pair Node to select it. The Properties window displays the properties for the selected component.

      Note:

      If the Properties window is not visible, select Properties from the Window main menu.

   2. In the Properties window, change the name and description, as desired.

   3. Click Save in the Oracle JDeveloper toolbar.

4. To add stages to the pipeline, see Adding Stages to Pipelines in JDeveloper.

5. To add actions to stages in the pipeline. See Adding and Editing Actions in Pipelines in JDeveloper.

6. On the Pipeline Editor, continue to construct the pipeline, as described in Viewing and Editing Pipelines in JDeveloper.

7. Click Save in the Oracle JDeveloper toolbar.

16.5 Adding Conditional Branches to Pipelines in JDeveloper

A branch node allows processing to proceed along exactly one of several possible paths. Branching is driven by an XPath-based switch table. Each branch in the table specifies a condition (for example, <500) that is evaluated in order down the pipeline against a single XPath expression (for example, ./ns: PurchaseOrder/ns:totalCost on $body). Whichever condition is satisfied first determines which branch is followed. If no branch condition is satisfied, then the default branch is followed. A branch node may have several descendants in the pipeline: one for each branch, including the default branch.

If the proxy service is not based on a WSDL file and receives multiple document types as input, you can consider using a conditional branch node.

Conditional branching is driven by a lookup table with each branch tagged with a simple, but unique, string value. A variable in the message context is designated as the lookup variable for that node, and at runtime, its value is used to determine which branch to follow. If no branch matches the value of the lookup variable, the default branch is followed. You should design the proxy service in such a way that the value of the lookup variable is set before reaching the branch node.

16.5.1 How to Add a Conditional Branch to a Pipeline in JDeveloper

Use the Pipeline Editor to add a conditional branch to the message flow for the pipeline.

To add a conditional branch to a pipeline:

1. In the Pipeline Editor, right-click the start node icon) or a Branch Node icon.

2. Select Insert Into > Conditional Branch from the context menu that appears.The conditional branch node is added, and any existing nodes after the inserted branch node are moved to the default branch of the new conditional branch node.

   Note:

   You can alternatively choose to drag a Conditional Branch component from the Components window to the appropriate location in the Pipeline Editor. The Conditional Branch component can be found under the Nodes section of the Message Flow category.

3. To change the properties for the conditional branch node, do the following:

   1. Click the Conditional Branch node to select it. The Properties window displays the properties for the selected component.

      Note:

      If the Properties window is not visible, select Properties from the Window main menu.

   2. Under the General section, change the name and description, as desired.

   3. Under the Condition section, specify an XPath expression to use as the condition. You can invoke the XPath Expression Builder by clicking the fx icon.

   4. Click Save in the Oracle JDeveloper toolbar.

4. To change the properties for a branch, do the following:

   1. Click the branch node to select it. The Properties window displays the properties for the selected component.

      Note:

      If the Properties window is not visible, select Properties from the Window main menu.

   2. Under Name, specify a name for the branch.

   3. Under Value, specify an operator and an XPath expression to use as the value. You can invoke the XPath Expression Builder by clicking the fx icon.

   4. Click Save in the Oracle JDeveloper toolbar.

5. Optionally:

   • Click the Add New Branch icon to add a new branch node.

   • Right-click a branch, and select Delete to delete the branch.

6. Click Save in the Oracle JDeveloper toolbar.

7. On the Pipeline Editor, continue to construct the pipeline, as described in Viewing and Editing Pipelines in JDeveloper.

8. Click Save in the Oracle JDeveloper toolbar.

16.6 Adding Operational Branches to Pipelines in JDeveloper

When pipelines define Web Services Description Language (WSDL)-based proxy services, operation-specific processing is required. Instead of configuring a branching node based on operations manually, Service Bus provides a minimal configuration branching node that automatically branches based on operations. In other words, when you create an operational branch node in a pipeline, you can quickly build your branching logic based on the operations defined in the WSDL file because the Oracle Service Bus Console presents those operations in the branch node configuration page.

A branch node allows processing to proceed along exactly one of several possible paths. Branching is driven by an XPath-based switch table. Each branch in the table specifies a condition (for example, <500) that is evaluated in order down the pipeline against a single XPath expression (for example, ./ns: PurchaseOrder/ns:totalCost on $body). Whichever condition is satisfied first determines which branch is followed. If no branch condition is satisfied, then the default branch is followed. A branch node may have several descendants in the pipeline: one for each branch, including the default branch.

16.6.1 How to Add an Operational Branch to a Pipeline in JDeveloper

Use the Pipeline Editor to add an operational branch to the message flow for the pipeline.

To add an operational branch to a pipeline:

1. In the Pipeline Editor, right-click the start node or a Branch Node icon.

2. Select Insert Into > Operational Branch from the context menu that appears. The operational branch node is added, and any existing nodes after the inserted branch node are moved to the default branch of the new operational branch node.

   Note:

   You can alternatively choose to drag an Operational Branch component from the Components window to the appropriate location in the Pipeline Editor. The Operational Branch component can be found under the Nodes section of the Message Flow category.

3. To change the properties for the operational branch node, do the following:

   1. Click the operational branch node to select it. The Properties window displays the properties for the selected component.

      Note:

      If the Properties window is not visible, select Properties from the Window main menu.

   2. Change the name and description, as desired.

   3. Click Save in the Oracle JDeveloper toolbar.

4. To change the properties for a branch, do the following:

   1. Click the branch node to select it. The Properties window displays the properties for the selected component.

      Note:

      If the Properties window is not visible, select Properties from the Window main menu.

   2. Select the Operation represented by the branch.

   3. Click Save in the Oracle JDeveloper toolbar.

5. Optionally:

   • Click the Add New Branch icon to add a new branch node.

   • Right-click a branch, and select Delete to delete the branch.

6. On the Pipeline Editor, continue to construct the pipeline, as described in Viewing and Editing Pipelines in JDeveloper.

7. Click Save in the Oracle JDeveloper toolbar.

16.7 Adding REST Branches to Pipelines in JDeveloper

When pipelines define native, untyped (no WADL at design time), REST-based proxy services, client request-specific processing is required. Instead of configuring a branching node based on these requests manually, Service Bus provides a minimal configuration branching node that automatically branches based on media type consumed, relative URI, HTTP Verb, or a combination of these criteria. When you create a REST branch node in a pipeline, you can quickly build your branching logic based on these criteria.

You can configure the following options to filter client requests:

• Consumes Media Types: a list of media types sent by a client that are allowed for this branch, such as application/json.

• Path: a single URI pattern (relative URI path) allowed for this branch. For example, /dogs/{id} is a valid path.

• Verb: a single HTTP Verb (GET, PUT, POST, or DELETE) allowed for this branch.

Note:

If the REST branch label contains a parameterized path expression, such as /name/{PlaceName}/zip/{ZipCode}, as part of the execution of REST branch, message context variables PlaceName and ZipCode are automatically defined with the values of the actual path segments at runtime, for example, Pittsburgh and 15217. The values of these parameters are extracted from inbound HTTP relative path metadata.

The scope of the variables is all of the actions nested in the corresponding branch

REST Branches can be used only in pipelines for native, untyped REST services; other service types are not supported.

16.7.1 How to Add a REST Branch to a Pipeline in JDeveloper

Use the Pipeline Editor to add a REST branch to the message flow for the pipeline.

To add a REST branch to a pipeline:

1. In the Pipeline Editor, right-click the start node or a Branch Node icon.
2. Select Insert Into > REST Branch from the context menu that appears. The REST branch node is added, and any existing nodes after the inserted branch node are moved to the default branch of the new REST branch node.

   Note:

   You can alternatively choose to drag a REST Branch component from the Components window to the appropriate location in the Pipeline Editor. The REST Branch component can be found under the Nodes section of the Message Flow category.

3. To change the properties for the REST branch node, do the following:
   1. Click the REST branch node to select it. The Properties window is displayed.

      Note:

      If the Properties window is not visible, select Properties from the Window menu.

   2. From the General tab, change the name , as desired.
   3. Click Save in the Oracle JDeveloper toolbar.
4. From the Branch tab of the Properties window, configure at least one of the following branch properties:

   • Consumes: Media Types: Click the Add (+) icon. Enter the name of a media type sent by the client request consumed by this branch, such as application/xml or application/json. You can enter multiple media types by clicking the Add (+) icon to add additional rows. Click the Delete (X) icon to remove a selected row.

     Note:

     Wildcards on type/subtype are supported. For instance, application/xml, examples/*, and */xml are supported. Partial wildcards, such as examples/*+xml, are not supported.

   • Path: Enter a relative URI patch for client requests consumed by this branch, such as /dogs/{id}.

   • Verb: Select the HTTP Verb for client requests consumed by this branch.

5. Optionally:
   1. Click the Add New Branch icon to add a new branch node.
   2. Right-click a branch, and select Delete to delete the branch.
6. On the Pipeline Editor, continue to construct the pipeline, as described in Viewing and Editing Pipelines in JDeveloper
7. Click Save in the Oracle JDeveloper toolbar.

16.8 Adding Stages to Pipelines in JDeveloper

Request pipelines, response pipelines, and error handlers can contain stages, where you configure actions to manipulate messages passing through the pipeline.

16.8.1 How to Add a Stage to a Pipeline in JDeveloper

Use the Pipeline Editor to add a stage to the message flow for the pipeline.

To add a stage to a pipeline:

1. In the Pipeline Editor, right-click a Request Pipeline icon or Response Pipeline icon in a pipeline pair node.

2. Select Insert Into > Stage from the context menu that appears. A stage node is added.

   Note:

   You can alternatively choose to drag a Stage component from the Components window to the appropriate location in the Pipeline Editor. The Stage component can be found under the Nodes section of the Message Flow category.

3. To change the default name and add a description for the stage, do the following:

   1. Click the stage node to select it. The Properties window displays the properties for the selected component.

      Note:

      If the Properties window is not visible, select Properties from the Window main menu.

   2. Edit the Name and Description fields for the selected stage node.

   3. Click Save in the Oracle JDeveloper toolbar.

4. To add actions to the stage, right-click the Stage icon, then click Insert Into > ActionName from the context menu that appears. See Adding and Editing Actions in Pipelines in JDeveloper.

5. To add error handling to the stage, right-click the Stage icon, then click Add Stage Error Handler from the context menu that appears. See Adding Error Handlers in JDeveloper.

6. Continue to construct the pipeline, as described in Viewing and Editing Pipelines in JDeveloper.

7. Click Save in the Oracle JDeveloper toolbar.

16.9 Adding Route Nodes to Pipelines in JDeveloper

A route node performs request/response communication with another service. It represents the boundary between request and response processing for the proxy service. When the route node dispatches a request message, the request processing is considered complete. When the route node receives a response message, the response processing begins. The route node supports conditional routing as well as request and response transformations.

Because a route node represents the boundary between request and response processing, it cannot have any descendants in the pipeline.

16.9.1 How to Add a Route Node to a Pipeline in JDeveloper

Use the Pipeline Editor to add a route node to the message flow for the pipeline.

To add a route node to a pipeline:

1. In the Pipeline Editor, right-click the start node or a Branch Node icon.
2. Select Insert Into > Route from the context menu. A route note is added.

   Note:

   You can alternatively choose to drag a Route component from the Components window to the appropriate location in the Pipeline Editor. The Route component can be found under the Nodes section of the Message Flow category.

3. To add actions to the route node, right-click the Route Node icon, then select the appropriate option from the context menu. See the following sections for information about the actions you can add to route nodes:

   • Adding If Then Actions in JDeveloper

   • Adding Dynamic Routing to Route Nodes in JDeveloper

   • Adding Routing Actions to Route Nodes in JDeveloper

   • Adding Routing Tables to Route Nodes in JDeveloper

   • Adding Error Handlers in JDeveloper

4. In the Pipeline Editor, continue to construct the pipeline, as described in Viewing and Editing Pipelines in JDeveloper.
5. Click Save in the Oracle JDeveloper toolbar.

16.10 Cutting, Copying, and Pasting Stages and Route Nodes in JDeveloper

You can cut, copy, and paste stages and route nodes in the Pipeline Editor.

• To cut a stage or a route node, right-click its icon and select Cut or Copy.

• To paste a stage that you cut or copied from a different pipeline pair within the message flow of the pipeline or from the message flow of a different pipeline, do one of the following:

  • Right-click the target Request Pipeline or Response Pipeline icon, then click Paste.

  • Right-click an existing Stage icon in a pipeline, then click Paste.

• To paste a route node that you cut or copied from the message flow of another pipeline, click the target Branch Node icon, then click Paste Route.

16.11 Configuring the Resequencer in JDeveloper

The resequencer in Service Bus rearranges a stream of related but out-of-sequence messages into a sequential order. When incoming messages arrive, they may be in a random order. The resequencer orders the messages based on sequential or chronological information, and then sends the messages to the target services in an orderly manner. The sequencing is performed based on the sequencing strategy selected.

You can configure the resequencer inside a pipeline component. Pipelines with the following service types are supported:

• WSDL: Resequencing is available for operations with only request type.

• Message Type: The request message type should be XML, and the response message type should be None.

Note:

The resequencer does not support Any XML and Any SOAP service types. For WSDL-based services, the WSDL file must be one-way; that is, it cannot contain output elements. For information about using generated WSDL files with resequencing pipelines, see How to Generate a WSDL File from a Service in JDeveloper.

16.11.1 How to Configure Resequencing in a Pipeline in JDeveloper

This section describes how to configure the resequencer in a pipeline using JDeveloper.

To enable resequencing in a pipeline:

1. Make sure you have the Service Bus project open in JDeveloper.
2. Use one of the following methods to edit the pipeline configuration:

   • In Application Navigator, locate the pipeline node. Right-click the pipeline node and select Open. You can alternatively double-click the pipeline node to open it.

   • In Application Navigator, click the project node (or overview.xml) to open the Overview Editor.

     In the Overview Editor, double-click the pipeline component to open the Pipeline Editor.

   The Pipeline Editor appears. Select the Configuration tab from the bottom left corner of the editor.

3. Select Resequencer from the left pane in the editor. The Resequencer Configuration page appears. Figure 16-4 shows the Resequencer Configuration page.

   Figure 16-4 Resequencer Configuration Page

   
   Description of "Figure 16-4 Resequencer Configuration Page"
4. Select Enable Resequencer to enable resequencing for the pipeline.
5. Select the Resequence Level. Choose Pipeline to configure resequencing at the component level. Choose Operations to configure resequencing at the operation level. See Selecting the Resequence Level in JDeveloper for more information on resequence levels.

   If you select Operations, you get the option to configure resequencing for each operation separately.

6. Select the Resequence mode. If you are configuring resequencing at the Operations level, then you can select a Resequence Mode corresponding to each operation. See How to Configure the Resequencing Mode in JDeveloper for more information on the various resequencing options.

   Depending on the Resequence mode you select, you get options corresponding to that mode. For example, selecting the Standard mode requires you to select values for Group, Id, and so on. Figure 16-5 shows the resequencer configuration options that appear when you select the Standard mode.

   Figure 16-5 Resequencer Options for the Standard Resequence Mode

   
   Description of "Figure 16-5 Resequencer Options for the Standard Resequence Mode"
7. Enter a Dispatch Policy, which specifies the Work Manager to use. The default Work Manager is used if no other Work Manager exists.
8. Click Save in the JDeveloper toolbar.

16.11.2 Selecting the Resequence Level in JDeveloper

You can define resequencing either at the pipeline level or the operation level. The Resequence Level can have the following values:

• Pipeline: A common configuration specified at the component level is used to resequence all messages. If a component has multiple operations, then messages for each operation are sequenced separately using the common component configuration.

  Component-level resequencing is allowed only when all the operations of the pipeline component support request one-way messages. If only a subset of operations support request one-way messages, then you can individually specify operation-level resequencing for these operations.

• Operations: For a WSDL-based pipeline, resequencing can be configured at the operation level. Each operation can have a different resequencer configuration. Only operations supporting request one-way messages can be resequenced. Non-WSDL pipelines cannot have resequencer configured at the operation level.

16.11.3 How to Configure the Resequencing Mode in JDeveloper

This section provides instructions on how to configure various resequencing modes. See "Resequencing Order" in Developing SOA Applications with Oracle SOA Suite to learn about the various resequencing modes. By default, the group ID has a character limit of 1000; the ID has a character limit of 100.

16.11.3.1 Configuring a Standard Resequencer

To configure a standard resequencer:

1. In the Resequencer Configuration page, select Standard from the Resequence drop-down list. If you are configuring resequencing at the operation level, select Standard from the Resequence Mode drop-down list for the operation.

   The Resequencer Options or Operation Details area is populated with fields related to standard resequencing. See Figure 16-5 for more details.

2. Fill in the fields listed in Table 16-1.

Table 16-1 Standard Resequencing Options

Field Name	Description	Default Value	Mandatory
Group	An XQuery expression that points to the field in the incoming message on which grouping is done. If you do not enter a value, then all messages are put in one default group. Click the Expression Builder icon on the right to invoke the XQuery Expression Builder.	N/A	N
ID	An XQuery expression that points to the field in the incoming message on which resequencing is done. Click the Expression Builder icon on the right to invoke the XQuery Expression Builder.	N/A	Y
Start	The starting number of the ID sequence.	1	N
Increment	The increment of the ID sequence.	1	N
Timeout	The time period in seconds to wait for an expected message. The resequencer locks the group as timed-out if a time out occurs. The default value of 0 means that the timeout never happens for a group by default.	0	N

16.11.3.2 Configuring a FIFO Resequencer

To configure a FIFO resequencer:

1. In the Resequencer Configuration page, select FIFO from the Resequence drop-down list. If you are configuring resequencing at the operation level, select FIFO from the Resequence Mode drop-down list for the operation.

   The Resequencer Options or Operation Detail area is populated with fields related to FIFO resequencing.

2. In the Group field, enter an XQuery expression pointing to the field in the incoming message on which grouping is performed.

   Click the Expression Builder icon on the right to invoke the XQuery Expression Builder

16.11.3.3 Configuring a Best Effort Resequencer

To configure a best effort resequencer:

1. In the Resequencer Configuration page, select Best Effort from the Resequence drop-down list. If you are configuring resequencing at the operation level, select Best Effort from the Resequence Mode drop-down list for the operation.

   The Resequencer Options or Operation Detail area is populated with fields related to Best Effort resequencing.

2. Fill in the fields listed in Table 16-2 to configure the best effort resequencer.

   Table 16-2 Best Effort Resequencing Options

   Field Name	Description	Default Value	Mandatory
   Group	An XQuery expression that points to the field in the incoming message on which grouping is performed.If no value is entered here, then all messages are considered to be in one default group. Click the Expression Builder icon on the right to invoke the XQuery Expression Builder.	N/A	N
   ID	An XQuery expression that points to the field in the incoming message that contains the ID on which resequencing is performed. Click the Expression Builder icon on the right to invoke the XQuery Expression Builder.	N/A	Y
   Datatype	The data type of the sequence ID. The ordering process is based on the data type. Supported values are Date/Time and Numeric.	Numeric	Y
   Max Rows	Number of in-sequence messages that the resequencer should pick from the data store at a time. This must be a positive integer value. You must specify Max Rows or Time Window (explained below), but not both.	5	N
   Time Window (sec)	The length of time in seconds to wait after a message arrives before selecting messages from the data store for resequencing. The default value of 0 means no wait. You must specify a Time Window or Max Rows (described above), but not both.	0	N