spring - Why should i add state? -

hi, error , don't know why ??

start state missing. add @ least 1 state flow

file : main-flow.xml

<?xml version="1.0" encoding="utf-8"?> <flow xmlns="http://www.springframework.org/schema/webflow" xmlns:xsi="http://www.w3.org/2001/xmlschema-instance" xsi:schemalocation="http://www.springframework.org/schema/webflow     http://www.springframework.org/schema/webflow/spring-webflow-2.3.xsd">  <view-state id="start" view="start.xhtml">  </view-state> 

file pom.xml

 <dependency>         <groupid>org.springframework.webflow</groupid>         <artifactid>spring-webflow</artifactid>         <version>2.3.1.release</version>     </dependency> 

you have add start-state parameter flow tag.

<?xml version="1.0" encoding="utf-8"?> <flow xmlns="http://www.springframework.org/schema/webflow" xmlns:xsi="http://www.w3.org/2001/xmlschema-instance" xsi:schemalocation="http://www.springframework.org/schema/webflow     http://www.springframework.org/schema/webflow/spring-webflow-2.3.xsd" start-state="start"> 

an end-state not requirement work of-course recommended have end state clean resources instance.

<end-state id="end"/>