### Operational Branch Node Properties

In a message flow, use an operational branch node to configure branching based on operations defined in a WSDL.

When message flows define WSDL-based proxy services, operation-specific processing is required. Instead of configuring a branching node based on operations manually, ALSB provides a branching node that automatically branches based on operations. In other words, when you create an operational branch node in a message flow, you can quickly build your branching logic based on the operations defined in the WSDL, because the ALSB plug-in presents those operations in the operational 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 message flow 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 message flow: one for each branch, including the default branch.

When you add an operational branch node to a message flow in the Message Flow Editor, the node contains an initial conditional branches based on the first operation defined in the WSDL, as shown below, plus a default branch:

Click the node itself (the Operational Branch Node icon or the bounding box connected to the icon) to display the Flow properties page in the Properties view. You can provide a name and a description for the node on that page.

Click an operational branch icon to display the properties for that operational branch on the Operational Branch page. That page contains a drop-down list of all the operations defined in the WSDL. You can select a different operation for that branch. You can also click the plus sign in the operational branch node, in the Message Flow Editor, to add another operation branch.

After you have added all the branches, add nodes and stages to them to define the processing for each branch.