Question

I’m working on a simple UI through which users can add a message to our announcement system.

They enter details onto addMessage.jsp, review the results on reviewMessage.jsp, and then submit from reviewMessage.jsp, where the information will be sent to a database via stored procedure.

Everything works fine, until the user gets to the submit from the review page. When execution leaves the JSP and re-enters the Action class, the message bean has become null. How do I persist the bean through multiple methods and pages in the same action?

Here’s a snippet of my struts.xml file:

<!--Render message entry page-->
<action name="activateMessageInitial"
    class="org.mycompany.struts.action.ActivateMessageAction" method="execute">
    <result name="success">/addMessage.jsp</result>
</action>

<!--Receive message bean fields, adjust their results for storage, render review page-->        
<action name="segmentMessage"
    class="org.mycompany.struts.action.ActivateMessageAction" method="parseAndSegment">
    <result name="failed">/addMessage.jsp</result>
    <result name="success">/reviewMessage.jsp</result>
</action>

<!--Review complete, break message bean into fields to submit to database, then return to main menu-->      
<action name="submitMessage"
    class="org.mycompany.struts.action.ActivateMessageAction" method="activate">            
    <result name="success" type="redirectAction">main</result>
</action>   

And an obfuscated ActivateMessageAction class:

private TargetedMessage messageBean;

public String execute() throws Exception 
{           
    //empty method  
}

//Take the provider message bean, adjust any values as necessary, and then add in the segmentation detail.
public String parseAndSegment() throws Exception    
{       
    //adjust bean fields
}

//Take a completed provider message bean and send it to the database for processing.
public String activate()
{

    //send bean to database; null, here, hence the error.
    ActivateMessageModel.createMessage(messageBean);    
}

public void setMessageBean(TargetedMessage messageBean)
{
    this.messageBean = messageBean;
}

public TargetedMessage getMessageBean()
{
    return messageBean;
}

Answer 1

The lifecycle of an action is limited to a single HTTP request. You can either pass the data as hidden form fields or store the object in session.