Both recursiveTreeNodesAdaptor & treeNodesAdaptor (model adaptor components further in the text) components allow defining data model declaratively and binding treeNode components to tree model nodes. treeNodesAdaptor has a "nodes" attribute that's used to define a collection of elements to iterate through. Collections are allowed to include: lists, arrays, maps, XML NodeList & NamedNodeMap either as single object. The current collection element is accessible via a request-scoped variable named as "var" attribute value.

recursiveTreeNodesAdaptor is an extension of a treeNodesAdaptor component that allows you to define two different value expressions: the first, assigned by "roots" attribute is used at the top of recursion, the second "nodes" is used on another recursion levels (the second level and deeper).

Example

org

richfaces

demo

datatablescroller

datatable

treemodeladaptor

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<ui:composition xmlns="http://www.w3.org/1999/xhtml"
      xmlns:ui="http://java.sun.com/jsf/facelets"
      xmlns:h="http://java.sun.com/jsf/html"
      xmlns:f="http://java.sun.com/jsf/core"
      xmlns:a4j="http://richfaces.org/a4j"
      xmlns:rich="http://richfaces.org/rich">

    <h:form>    
        <rich:tree style="width:300px" switchType="ajax" stateAdvisor="#{treeDemoStateAdvisor}">
            <rich:recursiveTreeNodesAdaptor roots="#{fileSystemBean.sourceRoots}" var="item" nodes="#{item.nodes}" />
        </rich:tree>
    </h:form>

</ui:composition>

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HideView FileSystemBean.java Source

package org.richfaces.treemodeladaptor;


public class FileSystemBean {
    private static String SRC_PATH = "/WEB-INF/src";
    
    private FileSystemNode[] srcRoots;
    
    public synchronized FileSystemNode[] getSourceRoots() {
        if (srcRoots == null) {
            srcRoots = new FileSystemNode(SRC_PATH).getNodes();
        }
        
        return srcRoots;
    }
}

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HideView FileSystemNode.java Source

package org.richfaces.treemodeladaptor;

import java.util.Set;

import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;

public class FileSystemNode {
    private String path;

    private static FileSystemNode[] CHILDREN_ABSENT = new FileSystemNode[0];
    
    private FileSystemNode[] children;

    private String shortPath;
    
    public FileSystemNode(String path) {
        this.path = path;
        int idx = path.lastIndexOf('/');
        if (idx != -1) {
            shortPath = path.substring(idx + 1);
        } else {
            shortPath = path;
        }
    }

    public synchronized FileSystemNode[] getNodes() {
        if (children == null) {
            FacesContext facesContext = FacesContext.getCurrentInstance();
            ExternalContext externalContext = facesContext.getExternalContext();
            Set resourcePaths = externalContext.getResourcePaths(this.path);
            if (resourcePaths != null) {
                Object[] nodes = (Object[]) resourcePaths.toArray();
                children = new FileSystemNode[nodes.length];
                
                for (int i = 0; i < nodes.length; i++) {
                    String nodePath = nodes[i].toString();
                    if (nodePath.endsWith("/")) {
                        nodePath = nodePath.substring(0, nodePath.length() - 1);
                    }
                    children[i] = new FileSystemNode(nodePath);
                }
            } else {
                children = CHILDREN_ABSENT;
            }
        }

        return children;
    }
    
    public String toString() {
        return shortPath;
    }

}

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HideView PostbackPhaseListener.java Source

package org.richfaces.treemodeladaptor;

import java.util.Map;

import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;
import javax.faces.event.PhaseEvent;
import javax.faces.event.PhaseId;
import javax.faces.event.PhaseListener;

public class PostbackPhaseListener implements PhaseListener {

    public static final String POSTBACK_ATTRIBUTE_NAME = PostbackPhaseListener.class.getName();
    
    public void afterPhase(PhaseEvent event) {
    }

    public void beforePhase(PhaseEvent event) {
        FacesContext facesContext = event.getFacesContext();
        Map requestMap = facesContext.getExternalContext().getRequestMap();
        requestMap.put(POSTBACK_ATTRIBUTE_NAME, Boolean.TRUE);
    }

    public PhaseId getPhaseId() {
        return PhaseId.APPLY_REQUEST_VALUES;
    }

    public static boolean isPostback() {
        FacesContext facesContext = FacesContext.getCurrentInstance();
        if (facesContext != null) {
            ExternalContext externalContext = facesContext.getExternalContext();
            if (externalContext != null) {
                return Boolean.TRUE.equals(
                        externalContext.getRequestMap().get(POSTBACK_ATTRIBUTE_NAME));
            }
        }
        
        return false;
    }
    
}

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HideView TreeDemoStateAdvisor.java Source

package org.richfaces.treemodeladaptor;

import org.richfaces.component.UITree;
import org.richfaces.component.state.TreeStateAdvisor;
import org.richfaces.model.TreeRowKey;

public class TreeDemoStateAdvisor implements TreeStateAdvisor {

    public Boolean adviseNodeOpened(UITree tree) {
        if (!PostbackPhaseListener.isPostback()) {
            Object key = tree.getRowKey();
            TreeRowKey treeRowKey = (TreeRowKey) key;
            if (treeRowKey == null || treeRowKey.depth() <= 2) {
                return Boolean.TRUE;
            }
        }
        
        return null;
    }

    public Boolean adviseNodeSelected(UITree tree) {
        return null;
    }

}

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Model adaptor components can be nested without any limitations. The following code-snippet shows an example of using Nodes Adapter along with rich:tree

Data model nodes are wired to treeNode components by nesting treeNode components with a "type" attribute not defined inside model adaptor components. The first rendered one is used, or the default one if all treeNode components are non-rendered.