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POFaking Recursion in JSF
 

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    <p>I'm trying to display a tree in JSF without hard-coding the depth of the tree I want to display. Maybe for one configuration I only want to show the leaves, maybe for another I want to show the leaves grouped by the nodes one level above them, etc. So for one configuration, it could be:</p> <p><b><ul> <li>Question 1</li> <li>Question 2</li> <li>Question 3</li> <li>Question 4</li> </ul> </b></p> <p>While for another configuration, the same underlying data structure could produce:</p> <p><b><ul> <li>Category 1:</li></p> <ul> <li>Question 1</li> <li>Question 2</li> </ul> <p><li>Category 2:</li></p> <ul> <li>Question 3</li> </ul> <p><li>Category 3:</li></p> <ul> <li>Question 4</li> </ul> <p></ul> </b></p> <p>With a hypothetical third configuration grouping the categories by super-categories, etc.</p> <p>I tried making a composite component that called itself recursively if the node had more children. I did this via <code>&lt;ui:fragment rendered="#{node.hasChildren}"&gt;</code> and -- surprise! -- this resulted in an infinite loop and a stack overflow.</p> <p>The project already has PrimeFaces installed, so I'm looking at PrimeFaces <code>Tree</code> and <code>TreeNode</code>. But that doesn't quite feel right; I don't want the tree nodes to be expandable in the user interface. I want everything to be fully expanded. I haven't gone too deeply down this rabbit hole so I suspect there may be a way to achieve this with <code>Tree</code>, but it feels like I'm going against the grain of what it's built to do.</p> <p>What's a good approach this problem?</p> <p><hr /> <b>Edit:</b> I'm trying to use &lt;tree> and &lt;treeNode>, but it's not working. My code looks like this:</p> <pre><code>&lt;p:tree value="#{cc.attrs.classification}" var="child"&gt; &lt;p:treeNode&gt; &lt;ui:fragment rendered="#{child.childCount &gt; 0}"&gt; [do node stuff] &lt;/ui:fragment&gt; &lt;ui:fragment rendered="#{child.childCount == 0}"&gt; [do leaf stuff] &lt;/ui:fragment&gt; &lt;/p:treeNode&gt; &lt;/p:tree&gt; </code></pre> <p>... where <code>classification</code> implements the <code>TreeNode</code> interface. This results in errors to the console complaining that <code>child</code> is of type String and therefore cannot do any of the interesting things I'm asking of it. What am I doing wrong?</p>
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