Struts: FormBean does not see String[] from JSP

Hi Experts,

I have a JSP page that needs to select a list of userIDs. The list of userIDs are populated from the database on a different JPS page. I need to pass this list of userIDs back to the original JPS page (the caller).
Some how my FormBean does not see this list. It is throwing a NullPointerException.

Here is my JSP code
<html:select property="subscriberList" multiple="multiple">
<%
int nRows = abean.getSubscribersList();
String subscriberName = null;

for (int i=0; i < nRows; i++){
subscriberName = abean.getString("UserID");
abean.moveNext();%>
<html

ption value="<%=subscriberName%>"> <%=subscriberName%></html

ption>
<%}%>
</html:select></TD>

Here is my FormBean code. Only one of these variables should be used but currently both of them are null.

private String subscriberName = null;
private String [] subscriberList = {};

/**
* Returns the subscriberList.
* @return String[]
*/
public String[] getSubscriberList() {
return subscriberList;
}

/**
* Sets the subscriberList.
* @param subscriberList The subscriberList to set
*/
public void setSubscriberList(String[] subscriberList) {
this.subscriberList = subscriberList;
}

/**
* Returns the subscriberName.
* @return String
*/
public String getSubscriberName() {
return subscriberName;
}

/**
* Sets the subscriberName.
* @param subscriberName The subscriberName to set
*/
public void setSubscriberName(String subscriberName) {
this.subscriberName = subscriberName;
}

Any help is greatly appreciated!

Yen

I think this really belongs in the Struts or JSP forum.

However, not seeing the rest of the code I do not know whether this is
all of the problem but if

is meant to be a call to

in FormBean, then you are trying to assign a String[] to an int.
If you have them spelled correctly in you OP, and it is not a typo, then disregard my comment as they are clearly different methods.

Also, is aBean in scope?

Hi Edward,

Thank you for your reply...

I did not make a typo. How do I fix this problem?

aBean is in scope. I got the data back from the DAO fine. I cannot save this subscribersList, which will be passed back to another form.

Can you help me resolve this? How would you do this?

Thanks,
Yen

Moved to the Struts forum.

First of all, the line:

int nRows = abean.getSubscribersList();

Does not look right to me. I would expect a method named "getSubscribersList" to return a list of subscribers, not the number of subscribers. Are you sure this shouldn't be:

int nRows = abean.getSubscribersList().size();

?

As for your NullPointerException: Where is it occurring? In the JSP code, or in the ActionForm code? Can you show us the stack trace for the error?

Hi Merrill,

Thank you for your suggestion...

I'll try it and let you know.

Thanks,
-Kayla

I am still unable to get this problem resolved.

Does anyone has an example how to generate a list of users from JSP page and save them in the Form??

Your help is appreciated!

-Kayla

Hi hope this helps!!

<%@ page language="java" import="java.util.ArrayList" %>

<%@ taglib uri="struts-bean.tld" prefix="bean" %>
<%@ taglib uri="struts-html.tld" prefix="html" %>
<%@ taglib uri="struts.tld" prefix="struts" %>

<bean

efine id="subscriberList" name="formBean" property="subscriberList" type="java.util.Collection"/>

<HEAD>

</HEAD>

<table border="0" cellpadding="1" cellspacing="1">
<tr>
<td>Existing subscribers</td>
<td> <html:select property="subscriberName" styleClass="dropdownMenu">
<html

ptions collection="subscriberList" property="value"/>
</html:select></td>
</tr>

</table>

//to be implemented in Action class

FormBean formBean =null;
formBean = (FormBean)form;
Arraylist subscriber_list=<get your arraylist of subscribers from backend>
formBean.setSubscriberList(subscriber_list);

//to be implemented in Action Form

private Collection subscriberList = new ArrayList();

/**
* Returns the subscriberName.
* @return String
*/
public String getSubscriberName() {
return this.subscriberName;
}

/**
* Sets the subscriberName.
* @param subscriberName The subscriberName to set
*/
public void setSubscriberName(String subscriberName) {
this.subscriberName = subscriberName;
}

/**
* Return the subscriber list.
*/
public Collection getsubscriberList() {

return (this.subscriberList);

}

/**
* Set the subscriber list.
*
*
*/
public void setsubscriberList(Collection subscriberList) {

this.subscriberList = subscriberList;

}

[ June 27, 2006: Message edited by: Christian Nash ]

Hi Christan,

Your example would work if my subscriberList is retrieved from the DB and remains unchanged.

The problem is I have to save the new subscriberList after the user selects them.

Here is what I have to do...
1) Create a 2 columes window. On the left I show the available Users, and on the right I show the current Subscribers.
2) In order to select from left to right or right to left, I provide the << or >> buttons.
3) The user can select from either box and click <Submit>. When this happens, I need to save the Current Subscribers only (subscriberList) ignore the Available Users

Currently I can save the Current Subscribers that I retrieved from the DB into an ArrayList. But I DON'T know how to save the newly selected subscriberList.

Thanks,
Kayla