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Accesssing model attribute in JPA doesn't work

I am having problems accessing a model attribute in my controller, using Spring.
When adding to the model, I write the status code as a key and the enumeration name as a value. The status code is e.g. AVAILABLE, NOTAVAILABLE, etc.:
String code = status.getCode();
String enumerationName = enumerationService.getEnumerationName(status, currentLocale);
model.addAttribute(code, enumerationName);
On my JPA page, I am trying to access the corresponding value using the key (status code, e.g. AVAILABLE):
<div data-availability>
<c:forEach items="${StockLevelDeliveryStatus.values()}" var="status">
<c:set var="textStyle" value="text-success" />
<c:if test="${status.code.toLowerCase() == 'notavailable'}">
<c:set var="textStyle" value="" />
</c:if>
<div class="d-none display-22 pb-2 ${textStyle}" data-availability-item data-${status.code.toLowerCase()}>
${status}
</div>
</c:forEach>
</div>
For example, the value of status is AVAILABLE and this is what is output in ${status}. However, I want the value AVAILABLE to be used as a key to return me the correct value that I set in the model above. If I change the ${status} statement to, say, ${AVAILABLE} instead, which is the concrete key, the appropriate value from the model is returned:
<div class="d-none display-22 pb-2 ${textStyle}" data-availability-item data-${status.code.toLowerCase()}>
${AVAILABLE}
</div>
If I understand it correctly, then instead of passing the enum value as a key, I need to somehow teach Spring to search in the model for the appropriate key.
As recommended in one of the replies, I also tried writing the Map<StockLevelDeliveryStatus, String> directly into the model:
Map<StockLevelDeliveryStatus, String> statusMap = new HashMap<StockLevelDeliveryStatus, String>();
for (StockLevelDeliveryStatus status : StockLevelDeliveryStatus.values()) {
statusMap.put(status, enumerationService.getEnumerationName(status, currentLocale));
}
model.addAttribute("statusMap", statusMap);
And the JSP accordingly:
<div data-availability>
<c:forEach items="${StockLevelDeliveryStatus.values()}" var="status">
<c:set var="textStyle" value="text-success" />
<c:if test="${status.code.toLowerCase() == 'notavailable'}">
<c:set var="textStyle" value="" />
</c:if>
<div class="d-none display-22 pb-2 ${textStyle}" data-availability-item data-${status.code.toLowerCase()}>
${statusMap[status]}
</div>
</c:forEach>
</div>
Here it already fails when accessing the model, because with this approach I do not get any output on the JSP.
Does anyone have any ideas on how to make this work?

Why not simply put a Map<StockLevelDeliveryStatus, String> into the model? You could then simply use ${statusMap[status]}.

How to pass an array of HashMaps to partial

I'm building an app with Java and Thymeleaf and I need to pass a HashMap to a partial. I don't want to pass it from a controller.
This is what I tried so far:
user.html
<div th:replace="partials/icons.html :: icons(icons=${ {name='user', title='User'}, {name='blog', title='Blog'} })"></div>
/partials/icons.html
<div th:fragment="icons">
<th:block th:each="icon : ${icons}">
<button th:class="'icon-' + ${icon.name}" th:text="${icon.title}"></button>
</th:block>
</div>
It gives me an error that = is unexpected. What would be the correct syntax?

EDIT: I should have clarified up-front: there is no way to do what you are trying to do with the syntax of fragment parameters. My approach below is a work-around.
Assuming you have the following object as a starting point:
public class Icon {
private String name;
private String title;
// getters and setters...
}
Assuming you then have a List of such objects, called icons...
This list is passed to your Thymeleaf renderer in the usual way. I don't use Spring, so how you do that is (I assume) through an annotation. I may be wrong - it shouldn't affect the approach below, however. In my no-Spring approach the list is added to the Thymeleaf model as map.put("icons", icons);
I have the following in my parent Thymeleaf template:
<div th:replace = "/iconsfragment.html :: icons(iconlist='icons')">
</div>
I have the following in iconsfragment.html:
<div th:fragment="icons(iconlist)">
<th:block th:each="icon : ${__${iconlist}__}">
<div th:class="'icon-' + ${icon.name}" th:text="${icon.title}"></div>
</th:block>
</div>
It uses a preprocessor __${...}__ to convert the parameter (a string) back into an iterable object.
The resulting HTML that you care about is:
<div class="icon-firstName">firstTitle</div>
<div class="icon-secondName">secondTitle</div>
This only really makes sense if you want to re-use that fragment in various different ways, of course. Otherwise just pass the ${icons} object directly to the fragment.
And my <div> example would of course need to be adapted to your <button> example.

How to handle buttons with same value but different names in Spring

I have a table that is dynamically created that has rows of movies.
It has a title column,
a media type column,
a rating column,
and a column that contains a "view" button.
When one of these view buttons is clicked,
I would like to go to a page that contains all the details of that movie by sending the title to the controller so I can query for it in mySql.
The problem is that for all these buttons,
the value is always going to be "view".
So my solution is to make the name of the button different as shown in the code below (this is the raw html generated from the jsp):
<html>
<body>
<form action="someAction">
<table>
<tr>
<th>title</th>
<th>type</th>
<th>rating</th>
</tr>
<tr>
<td>title1</td>
<td>DVD</td>
<td>R</td>
<td><input type="submit" name="mediaType.title1" value="view"></td>
</tr>
<tr>
<td>title2</td>
<td>DVD</td>
<td>R</td>
<td><input type="submit" name="mediaType.title2" value="view"></td>
</tr>
<tr>
<td>title3</td>
<td>BLU-RAY</td>
<td>PG-13</td>
<td><input type="submit" name="mediaType.title3" value="view"></td>
</tr>
</table>
</form>
</body>
</html>
I could then use a parameterMap to figure out which view was pressed.
That is messy and Spring has to have some way of being able to do this.
I thought something like this would work in the controller:
#RequestMapping("someAction", params = "mediaType.{title}=view")
public ModelAndView loadPage(String title) {
// use title to query mysql
// build Model
// return ModelAndView
}
However this doesn't work.
Is there something that I can use in Spring that would be simpler and cleaner like above instead of getting the parameterMap from the request?

If I'm understanding this correctly, you have rows of information organized into a table. You're looping through some kind of collection, which has the side effect of making each input field have similar 'name' attributes. As a result, it's difficult to determine which input fields you really care about. You've then chosen to use the button as an identifier (presumably, because only the one button you actually click on get's added to the request -all the others don't get submitted) to determine which 'row', and subsequent input fields.
I think this might all come down to which 'button' you're using. If you're using a literal input tag (type="submit" or "button") the 'value' attribute is what the user sees as the text on the button -so, you're forced to play shenanigans with the 'name' attribute (presumably by adding an index to the name, splitting the string once you get it out of the request, and using that identifier to get the other parameters out of the request that also have the same identifier appended to their 'name' attribute).
JSP
<input type="submit" name="view${varStatus.index}" value="View" />
HTML Source
<input type="submit" name="view3" value="View">
You should probably use the button tag instead. It allows the text that the user sees to be different than the value that is submitted in the request.
JSP
<button type="submit" name="view" value="${varStatus.index}" >View</button>
HTML Source
<button type="submit" name="view" value="3">View</button>
This gives you the 'identifier' for the row.
How Spring fits into this:
I played with the #RequestMapping and the #RequestParam annotations, and was unable to get Spring to give me the values directly into the controller. But, I was able to do it by writing a custom HandlerMethodArgumentResolver along with a custom annotation.
note: I'm using annotations and java config instead of xml config, AND probably more importantly -this was a quick and dirty example to get it working. adjust it as needed for your situation.
HandlerMethodArgumentResolver
Annotation
Controller method

Instead of putting the table inside one form, you could put multiple forms inside the table, in the TRs:
<tr>
<form action="someAction">
<td>title1<input type='hidden' name='title' value='title1' /></td>
<td>DVD</td>
<td>R</td>
<td><input type="submit" value="view"></td>
</form>
</tr>
Then each title has its own form and you send in the title (always with parameter name of title) from a hidden input.

The solution lies in this statement:
"I have a table that is dynamically created that has rows of movies".
Presumably,
you are looping through a list of movies and generating the table in the jsp file and each row has some unique identifier.
Add a hidden to identify the selected row.
Set the value of the hidden value in an onclick handler from the submit buttons.
Here is some example stuff:
<form ...>
<c:forEach blah var="row">
<tr>
...
<td><input type="submit" value="View" onclick="setSelectedRow('${row.id}')"/></td>
</c:forEach>
<input type="hidden" id="blammy" name="blammy" value=""/>
</form>
<script type="text/javascript">
function setSelectedRow(rowId)
{
... set blammy.value equal to rowId.
}
</script>
// the id is used by JavaScript to find the object in the DOM.
// the name is what appears in the request.
#RequestMapping("someAction")
public ModelAndView loadPage(
#RequestParameter("blammy") final String blammy)
{
...
}

How to bind a comma separated string to a Java collection (List) in Spring form?

I'm stuck in a situation where I've an input element in a JSP where user enters tags. E.g. java, foo, bar, anotherTag..etc
<c:url var="saveUrl" value="/create" />
<form:form modelAttribute="myAttribute" method="POST"
action="${saveUrl}">
<form:input path="myTitle" />
<form:textarea path="myPost" />
<form:input type="text" id="tagInput"path="???" />
<input type="submit" value="create" />
</form:form>
Now in my domain model corresponding to this input is a
private List<Tag> listOfTags
How to bind a csv to a List. If I enter listOfTags in the path(which is wrong for obvious reasons), I get incorrect binding exception.
How do I convert(or bind) a csv to a List so that the Spring form is submitted properly and the listOfTags get the tags entered in the JSP.
What is the best way to achieve it?
Please help.

I'm not sure but try this. Do a simple html input :
<input type="text" id="tagInput" name="myTags" />
And then in your controller do something like :
#RequestMapping(value="/create", method=RequestMethod.POST)
public void create(..., #ModelAttribute("myAttribute") MyClass myAttribute,
#RequestParam("myTags") String myTags, ...) {
...
myAttribute.setListOfTags(Arrays.asList(myTags.split(",")));
...
}
Note : for more generic ways to bind and convert objects, you may want to take a look at PropertyEditors and Converters.

I suggest try to bind it directly to listOfTags property. And to make it work just add contructor with one argument of String type (or define static method valueOf(String)) to Tag class.

Pretty sure you could do something like this:
<c:forEach var="i" begin="1" end="10">
<form:input type="text" path="listOfTags" />
</c:forEach>
Where you get the user to enter each tag into a separate text input. This is because Spring will automagically bind multiple inputs with the same form name to a List, when it does its binding.
You could use some jQuery sugar to only show one or two and then provide a widget to show more tag inputs. Or even write some cool JS to populate the inputs from a single text input just like StackOverflow does when you add tags.

Avoiding duplication in parameter name

Inside a POST in a .jsp file, I'd like to do something like this:
<input type="text" name="...">
And inside the servlet I'd like to do:
request.getParameter(...)
Now where should and how should I declare "..." so that I can avoid duplication and reuse the same String.
Should this go in an interface like this:
public interface SO {
String POST_PARAM = "userinput";
}
Or in a property file? Or ...?
In any case, how do I then access this from the .jsp and from the .java file?

You can define constants like final String POST_PARAM = "userinput"; and then use them in markup: <input type="text" name="<%=POST_PARAM%>">.
Moving fields names to properties file does not sound as a beneficial unless you have reasons to do this.
To get parameter value from HTTP request caused by form submit say request.getParameter(POST_PARAM).
I hope this helps.

You might get the ... from a bean using EL. However, it is not usual for me.

You can use standard actions: jsp:useBean, jsp:setProperty and JavaBean technology:
Example:
A.jsp should call HTTP POST to B.jsp. B.jsp should automatically map all fields and redirect to your servlet.
// model.MyBean.java
class MyBean {
private int age;
// getters&setters
}
// A.jsp:
<form method="POST" action="B.jsp">
<input type="text" name="age">
</form>
// B.jsp
<jsp:useBean id="form" class="model.MyBean" scope="request" />
<jsp:setProperty name="form" property="*" />
<jsp:include page="/servletURL" />
Small description:
MyBean class will be created. This bean should has exactly the same
fields name like name in your form: for <input type="text"
name="age"> in bean should exists int age field and getter/setter.
jsp:setProperty with wildcard map all values from form A.jsp into your bean automatically.
if you want to call your servlet you can simple include appropriate url. Then in the servlet you will have access to request attribute "form" which will has MyBean with entered values.