ui:repeat doesn't work with Map

icefaces, icefaces-2, jsf, jsf-2

Solution

UPDATE: JSF 2.3 (since 2017) supports this out of the box.

Unfortunately, `UIData` and `UIRepeat` have no support for iterating over a map in JSF.

If this bothers you (I guess it does), please vote for the following issue and if possible leave a comment that explains how you feel about this:

http://java.net/jira/browse/JAVASERVERFACES_SPEC_PUBLIC-479

In the mean time, you can iterate over a Map with some little helper code:

/**
 * Converts a Map to a List filled with its entries. This is needed since 
 * very few if any JSF iteration components are able to iterate over a map.
 */
public static <T, S> List<Map.Entry<T, S>> mapToList(Map<T, S> map) {

    if (map == null) {
        return null;
    }

    List<Map.Entry<T, S>> list = new ArrayList<Map.Entry<T, S>>();
    list.addAll(map.entrySet());

    return list;
}

Then define an EL function in a `*-taglib.xml` file like this:

<namespace>http://example.com/util</namespace> 

<function>
    <function-name>mapToList</function-name>
    <function-class>com.example.SomeClass</function-class>
    <function-signature>java.util.List mapToList(java.util.Map)</function-signature>
</function>

And finally use it on a Facelet like this:

<html xmlns:util="http://example.com/util">

    <ui:repeat value="#{util:mapToList(someDate)}" var="entry" >
        Key = #{entry.key} Value = #{entry.value} <br/>
    </ui:repeat>

Problem

I have a `Map` of key / values, which I initialize in `@PostConstruct` as follows: ``` Map<String, String> myMap; @PostConstruct public void init() { myMap=new LinkedHashMap<String, String>(); myMap.put("myKey","myValue"); } public Map<String, String> getMyMap() { return myMap; } public void setMyMap(Map<String, String> myMap) { this.myMap = myMap; } ``` When I try to iterate over this Map with `<ui:repeat>` like shown bellow, and I set a break point on the getter for the Map, I notice that it is not getting called, and so nothing is printed: ``` <ice:panelGroup> <ui:repeat items="#{myBean.myMap}" var="entry" varStatus="loop"> <input type="checkbox" name="myCheckBoxes" value="#{entry.value}" /> <span class="#{fn:contains(entry.value,'g') ? 'bold-style' : ''}">#{entry.key}</span> </ui:repeat> </ice:panelGroup> ``` But when replacing above code with `<c:foreach>`, everything works fine, and the list is printed as expected, any ideas why I am getting such behavior?

Original source

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