WSO2 Business Process Server v3.1.0 Documentation

##### Overview

- Home
- Release Note
- WS-BPEL Compliance
- License

##### Downloads

- Releases

##### Installation Guide

- Installing WSO2 BPS

##### Quick Start Guide

- Modeling the process
- Deploying the process
- Testing the process

##### User Guide

- Deploying BPEL Processes
- Deploying Human Tasks
- Managing BPEL processes
- Managing BPEL process instances
- QoS for BPEL processes
- Securing BPEL processes
- Invoking secured partner services
- Versioning
- Management API

##### Human Task Guide

- Human Tasks Quick Start Guide
- Deploying HumanTasks
- Managing Tasks
- Developing a Human Task Artifact
- Human Task Management and Configuration
- Human Task Concepts

##### Administrator Guide

- External data sources Configuration
- Registry Configuration
- Events
- Unified Endpoints
- BPEL Extensions
- Transaction Factory Configuration
- Message Exchange Interceptors
- OpenJPA specific properties
- JMS Transport Configuration
- Process Instance Cleanup Tasks
- Process Hydration and Dehydration
- Enabling Peer-to-Peer(P2P) Communication
- Setting up a BPS Cluster

##### Best Practices

- Process Deployment Best Practices

##### Concepts

- Process Versioning
- Process instance events
- Partner links

##### WS-BPEL Extensions

- Activity Failure and Recovery
- Extension Activities and Extensible Assign Operations
- XPath Extensions
- Iterable ForEach
- Flexible Assigns
- BPEL4People Extension

##### Samples

- HelloWorld
- If-Else
- ForEach
- While
- Repeat Until
- Flow and Links
- Pick
- Synchronous and Asynchronous Service Invocations
- Fault Handling
- Split
- XslTransform
- Compensation Handler
- Event Handler

##### Resources

- FAQ
- External Articles
- Library
- Source Code

##### Community

- Forum
- Mailing Lists

##### Project Information

- Issue Tracking

# Sample Guide - IF

### Table of Content

- Objective
- Prerequisites
- Overall Idea

### Objective

Shows how to use `<if/>` construct to implement where user need to verify a logical condition.

### Prerequisites

- Log in into BPS server admin console.
- Under Business Processes -> Add BPEL.
- Upload the TestIf.zip , (all samples are located at our sample repository.)
- Under the Business Processes -> Processes.
- Under the WSDL details widget -> Create instance

### Overall Idea

BPEL If-Else activity executes the process based on the condition defined in <condition/>. Comparing to pick activity, if-else activity depend on a logical condition rather on an event.

    <if>
        <condition>number($tmpVar)=number(2)</condition>
        <assign name="assignError">
            <copy>
                <from>
                    <literal>Worked</literal>
                </from>
                <to variable="myVar" part="TestPart"/>
            </copy>
        </assign>
        <else>
            <assign name="assignZut">
                <copy>
                    <from>
                        <literal>Failed</literal>
                    </from>
                    <to variable="myVar" part="TestPart"/>
                </copy>
            </assign>
        </else>
    </if>

`<condition/>` inside `<if/>` is used to implement the logical condition. Normally a XPath expression is used. `<else/>` is used to implement false case.

In the above example, value of `tmpVar` variable, is converted to a number and it's checked against 2. `<condition>number($tmpVar)=number(2)</condition>`

Based on the `tmpVar` value, `"TestPart"` element value in myVar variable will be `"Worked"` or `"Failed"`.

Note - Apache ODE runtime has default support for `http://www.w3.org/TR/xpath/`, where the `number($var)` is defined.