The document discusses how to use the choice component in Mule applications to conditionally route messages based on message properties. It provides an example Mule flow that sets a session property, logs it in two flows, and uses a choice component in the second flow to route the message based on whether the property equals "mule" or not. The choice component allows adding if/then/else logic to control message flow similar to programming code.

1. By
Sudha Ch

2.  The main motto of this PPT is how to use
Choice component in our applications.

3.  The choice flow control dynamically routes
messages based on message payload or
properties. It adds conditional programming
to a flow, similar to an if/then/elsecode
block.

5.  .mflow
 <?xml version="1.0" encoding="UTF-8"?>
 <mule xmlns:tracking="http://www.mulesoft.org/schema/mule/ee/tracking" xmlns:http="http://www.mulesoft.org/schema/mule/http"
xmlns:vm="http://www.mulesoft.org/schema/mule/vm" xmlns="http://www.mulesoft.org/schema/mule/core"
xmlns:doc="http://www.mulesoft.org/schema/mule/documentation" xmlns:spring="http://www.springframework.org/schema/beans" version="EE-3.4.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-current.xsd
 http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
 http://www.mulesoft.org/schema/mule/vm http://www.mulesoft.org/schema/mule/vm/current/mule-vm.xsd
 http://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd
 http://www.mulesoft.org/schema/mule/ee/tracking http://www.mulesoft.org/schema/mule/ee/tracking/current/mule-tracking-ee.xsd">
 <flow name="MessagePropertiesFlow1" doc:name="MessagePropertiesFlow1">
 <http:inbound-endpoint exchange-pattern="request-response" host="localhost" port="8089" path="choice" doc:name="HTTP"/>
 <message-properties-transformer scope="session" doc:name="Message Properties">
 <add-message-property key="property1" value="mule"/>
 </message-properties-transformer>
 <logger message="--flow1--#[sessionVars['property1']]" level="INFO" doc:name="Logger"/>
 <vm:outbound-endpoint exchange-pattern="request-response" path="messageproperties" doc:name="VM"/>
 </flow>
 <flow name="MessagePropertiesFlow2" doc:name="MessagePropertiesFlow2">
 <vm:inbound-endpoint exchange-pattern="request-response" path="messageproperties" doc:name="VM"/>
 <logger message="---flow2--#[sessionVars['property1']]" level="INFO" doc:name="Logger"/>
 <choice doc:name="Choice">
 <when expression="#[sessionVars['property1']=='mule']">
 <logger message="--the value of session property (property1) is 'mule'" level="INFO" doc:name="Logger"/>
 </when>
 <otherwise>
 <logger message="--the value of session property (property1) is not 'mule'" level="INFO" doc:name="Logger"/>
 </otherwise>
 </choice>
 </flow>
 </mule>

6.  Output:
 INFO 2015-10-03 16:00:23,705 [[messageproperties].config.change.14.thread.1]
org.mule.DefaultMuleContext:
 **********************************************************************
 * Application: messageproperties *
 * OS encoding: Cp1252, Mule encoding: UTF-8 *
 * *
 * Agents Running: *
 * Clustering Agent *
 * JMX Agent *
 **********************************************************************
 INFO 2015-10-03 16:00:23,706 [[messageproperties].config.change.14.thread.1]
org.mule.module.launcher.MuleDeploymentService:
 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 + Started app 'messageproperties' +
 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 INFO 2015-10-03 16:00:26,480 [[messageproperties].connector.http.mule.default.receiver.02]
org.mule.api.processor.LoggerMessageProcessor: --flow1--mule--studio
 INFO 2015-10-03 16:00:26,482 [[messageproperties].connector.http.mule.default.receiver.02]
org.mule.lifecycle.AbstractLifecycleManager: Initialising: 'connector.VM.mule.default.dispatcher.771015974'.
Object is: VMMessageDispatcher
 INFO 2015-10-03 16:00:26,482 [[messageproperties].connector.http.mule.default.receiver.02]
org.mule.lifecycle.AbstractLifecycleManager: Starting: 'connector.VM.mule.default.dispatcher.771015974'.
Object is: VMMessageDispatcher
 INFO 2015-10-03 16:00:26,489 [[messageproperties].connector.http.mule.default.receiver.02]
org.mule.api.processor.LoggerMessageProcessor: ---flow2--mule--studio

7.  Flow of execution:
1. URL to trigger the service from browser
http://localhost:8089/choice
2. session property is created using message
property component In flow1
3. Service displays session properties in flow1,
flow2
4. In flow2 the choice component checks the
value of the session property is ‘mule’ or not, if
true then it displays “the value of session
property (property1) is 'mule” else it goes and
displays data in default component

8.  https://docs.mulesoft.com/mule-user-
guide/v/3.5/choice-flow-control-reference