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Parameter passed to JSP via struts to JSP variable

Im a Java newbie, I have this code working which obtains the brandCode parameter and places in a hidden input named "brandCode"
<html:form method="get" action="/catalogindexsearch.do" styleId="sortAndNavigationForm">
<input type="hidden" name="formAction" value="searchDisplay" />
<html:hidden property="brandCode" />
</html:form>
But I wish to use the parameter elsewhere in my JSP i.e.
<h1>Brand Code: ${brandCode}</h1>
So my question is how can I create a Java variable from the html:form URL parameter?

In JSTL you can access a form property by form name
<h1>Brand Code: ${formName.brandCode}</h1>

Give it an ID like this:
<html:hidden property="brandCode" id="brandcode" />
then access the value by:
var brandCode = $("#brandcode").val();
or if you're not using jQuery:
var brandCode = document.getElementById("brandcode").value;
If you're trying to use the value of a property from your action class, you had it right - It's
${brandcode}
where brandcode is a property in your action class with getters and setters:
private String brandcode;
public String getBrandCode() {
}
you get the point.

What I was after in the end was this ${param.brandCode} or this ${param["brandCode"]}.

In Struts2, dynamically generate form element name using a member value

My requirement: In Struts 2, dynamically generate form element name by using member value.
I had tried with: <s:textarea name="employee_<s:property value='employeeNumber'/>"/>
Resulting code in web browser: <textarea name="employee_<s:property value='employeeNumber'/>"></textarea>
My expectation in web browser code: <textarea name="employee_101"></textarea>. 101 as an employeeNumber is only used for demonstration only.
Please help, thanks!

In Struts2 you can always use OGNL expression in the Struts tag's attribute. Just provide the value from the value stack. You should know that the action bean is on top of it, and having a getter for employeeNumber should return desired value 101.
<s:textarea name="employee_%{employeeNumber}"/>
Also be aware of Struts doesn't allow nested tags in the attributes in favor of OGNL.

try this,it working fine.
MyAction.class
private int property_value;
public int getProperty_value() {
return 6;
}
public void setProperty_value(int property_value) {
this.property_value = property_value;
}
result.jsp
<s:set var="xyz" value="property_value" />
<s:textarea name="emap_%{#xyz}" />

How to bind an object inside the list collection of the command object in Spring MVC

My command object have a list of objects. I want to bind a text field to the attribute of the object inside that list. Is it possible to do in Spring MVC?
Command object class
public class SubDevisonDto {
private String devId;
private List subDevisions;
Subdevision object class mentioned in the list
public class SubDivison implements Serializable{
private String subDivisonName;
private String createdBy;
private String createdDate;
private String developerID;
private List users;
I want text box to set the value for subDivisonName field.
I have written the Spring MVC tags like this.
<spring:bind path="subdivisondto.subDevisions[0].subDivisonName">
<span class="formw">
<input name="subDivisonName" type="text" style="width:350px;" />
</span>
</spring:bind>
Just for test purpose I have given it as 0. If it's working I can make it to a variable. my requirement is, I should let the user to dynamically add subdevision objects. So, initially when page is loading I will just show one text box. I will give a button for him to add if he want to add more. I will dynamically generate text boxes when he clicks the add button. After that I have to submit the form with the list.
This jsp code gives me an error. It says:
org.springframework.beans.NullValueInNestedPathException
Is there anyway for me to do this in jsp code?

I found the answer for my question. But, it's not the solution for my requirement as I need to implement a dynamic list. but I found a solution for this question.
As I understood, first time we have to send data from back end to bind input elements. I didn't find a way to bind form elements which takes input without sending a list data from beck end. But when we send data and bind the elements, we can take input from those elements. So, I think to bind the element in a situation like this we need to send data first time. Correct me if this statement is wrong. Because, that would be a more good solution for me.
We need to use the lazy list and jsp code is bit modified.
Your command class object should be created as below mentioned.
import org.apache.commons.collections.list.LazyList;
import org.apache.commons.collections.FactoryUtils;
public class SubDevisonDto {
private String devId;
private List subDevisions =
LazyList.decorate(
new ArrayList(),
FactoryUtils.instantiateFactory(SubDivison.class));
JSP code should look like below.
<c:forEach items="${subs.subDevisions}" var="obj" varStatus="gridRow">
Binding an input element text box
<spring:bind path="subdivisondto.subDevisions[${gridRow.index}].subDivisonName">
<span class="formw"><input name="<c:out value="${status.expression}"/>" type="text" style="width:350px;" />
binding an input element check box. This input element makes a list.
<spring:bind path="subs.subDevisions[${gridRow.index}].users">
<c:forEach items="${obj.users}" var="dependenttwo" varStatus="dependentRowtwo">
<li>
<input name="<c:out value="${status.expression}"/>" type="checkbox" class="users" value="<c:out value="${dependenttwo}"/>"/>
<c:out value="${dependenttwo}"/>
</li>
</c:forEach>
</spring:bind>
`subs` is a map key name. the value for this key `subs` is a list of my DTO objects which named as `SubDevisonDto `
This code works fine for me.
Thanks the support given.

In dto :
private List<SubDivision> SubDivisions = new AutoPopulatingList<SubDivision>(new SubDivisionFactory());
and factory would be something like:
public class SubDivisionFactory implements AutoPopulatingList.ElementFactory<SubDivision> {
public String createElement(int index) {
SubDivision subDivision = new SubDivision();
return subDivision;
}
}
using AutopopulatingList from spring. And your jsp will look the same, you can iterate over as many as you want.

Struts 2 s:submit button syntax to set values in map

I am browsing some Struts 2 code and I see this syntax for submit button that I haven't seen before..
<s:submit key="map.keyName$Value" />
It's not working (it was working with Struts 2.0.x now we have moved to Struts 2.2.3) any more. I mean its not setting the appropriate value based on the mentioned key in the map.
Has anyone used this syntax before?
Any other alternative syntax suggestions that will let me SET values in a map (using struts tag only) will be most welcome.
The jsp page containing this code is designed to be a decoupled component that can be included by any page at runtime that's why this page CANNOT call any java code to set these values in java map - which is why i am looking for tag solution that can set values in the map.
thanks in advance

Set value in a map by :
In JSP only
OGNL assignment statement :
<s:set var="" value="map[key] = keyValue" />
Java
<s:set var="" value="map.put(key, keyValue)" />
EDIT
You could set value in map (to action class) with
<s:hidden name="map[key]" value="keyValue" />
by submit button with onclick attribute, for example (answer - assume multiple submit button) :
<script type="text/javascript">
function setMap(key, keyValue) {
document.getElementById("mapToSet").name="map['" + key + "']";
document.getElementById("mapToSet").value=keyValue;
}
</script>
<s:hidden name="test" id="mapToSet" />
<s:submit value="Search" onclick="setMap(key, keyValue)" />

I found this page when searching for "how to set values in a map in Struts2" and it led me to the following answer (which I understand is a little OT):
As an HTML input element:
<input type="hidden" name="myField[105]" value="myValue" />
This would populate an action variable declared as:
Map<Integer, String> myField;
such that:
myField.get(105).equals("myValue"); // == true

How to update a the contents of a list displayed on JSP using Struts2?

I'm using Struts2 to display the contents of a list of objects on a JSP.
The flow of events is as following:
GetDataAction.java -> fetches values from
the database, fills in the ArrayList
named tableList. On success, the
displayData.jsp is shown.
displayData.jsp -> uses the s:iterate tag to display the values of objects
in the tableList.
The user changes some values in the
displayData.jsp and presses on the
Update button. On the click of
Update button, the
UpdateDataAction.java is called.
Now my problem is; How do I use the same tableList in UpdateDataAction.java to get the modified values?
I tried declaring an ArrayList with the same name 'tableList' (along with getters and setters), in UpdateDataAction.java but it throws a NullPointerException.
Please suggest.

IMO the way you are updating is not a good idea.Either you should link every row to a seperate edit page or use ajax.There are many plugins available to update table values using ajax,If you need i can provide you the links
Back to your way of doing it,i guess you are doing it as follows
<s:form action="UpdateDataActionName">
<s:iterator value="tableList">
<s:textfield name="objectName.propertyName1" value="%(propertyName1)">
<s:textfield name="objectName.propertyName2" value="%(propertyName2)">
<s:textfield name="objectName.propertyName3" value="%(propertyName3)">
</s:iterator>
<s:submit value="Update"/>
</s:form>
Now declare a list in your UpdateDataAction,of type <objectNameoftableListType> i.e. the same object type which the tabeList is representing.The name of the list must be objectName.Try to Iteate and check if you are getting the right values as submitted from the jsp.