SingleJcrNodeElem.java

   1 /*
   2  * Copyright (C) 2007-2012 Argeo GmbH
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package org.argeo.cms.ui.workbench.internal.jcr.model;
  17
  18 import javax.jcr.Node;
  19 import javax.jcr.NodeIterator;
  20 import javax.jcr.RepositoryException;
  21 import javax.jcr.Workspace;
  22
  23 import org.argeo.eclipse.ui.EclipseUiException;
  24 import org.argeo.eclipse.ui.TreeParent;
  25
  26 /**
  27  * UI Tree component. Wraps a node of a JCR {@link Workspace}. It also keeps a
  28  * reference to its parent node that can either be a {@link WorkspaceElem}, a
  29  * {@link SingleJcrNodeElem} or null if the node is "mounted" as the root of the
  30  * UI tree.
  31  */
  32 public class SingleJcrNodeElem extends TreeParent {
  33
  34         private final Node node;
  35         private String alias = null;
  36
  37         /** Creates a new UiNode in the UI Tree */
  38         public SingleJcrNodeElem(TreeParent parent, Node node, String name) {
  39                 super(name);
  40                 setParent(parent);
  41                 this.node = node;
  42         }
  43
  44         /**
  45          * Creates a new UiNode in the UI Tree, keeping a reference to the alias of
  46          * the corresponding repository in the current UI environment. It is useful
  47          * to be able to mount nodes as roots of the UI tree.
  48          */
  49         public SingleJcrNodeElem(TreeParent parent, Node node, String name, String alias) {
  50                 super(name);
  51                 setParent(parent);
  52                 this.node = node;
  53                 this.alias = alias;
  54         }
  55
  56         /** Returns the node wrapped by the current UI object */
  57         public Node getNode() {
  58                 return node;
  59         }
  60
  61         protected String getRepositoryAlias() {
  62                 return alias;
  63         }
  64
  65         /**
  66          * Overrides normal behaviour to initialise children only when first
  67          * requested
  68          */
  69         @Override
  70         public synchronized Object[] getChildren() {
  71                 if (isLoaded()) {
  72                         return super.getChildren();
  73                 } else {
  74                         // initialize current object
  75                         try {
  76                                 NodeIterator ni = node.getNodes();
  77                                 while (ni.hasNext()) {
  78                                         Node curNode = ni.nextNode();
  79                                         addChild(new SingleJcrNodeElem(this, curNode, curNode.getName()));
  80                                 }
  81                                 return super.getChildren();
  82                         } catch (RepositoryException re) {
  83                                 throw new EclipseUiException("Cannot initialize SingleJcrNode children", re);
  84                         }
  85                 }
  86         }
  87
  88         @Override
  89         public boolean hasChildren() {
  90                 try {
  91                         if (node.getSession().isLive())
  92                                 return node.hasNodes();
  93                         else
  94                                 return false;
  95                 } catch (RepositoryException re) {
  96                         throw new EclipseUiException("Cannot check children node existence", re);
  97                 }
  98         }
  99 }