+ refactoring of the JCR UI Model (in a MVC point of view)

[lgpl/argeo-commons.git] / server / plugins / org.argeo.jcr.ui.explorer / src / main / java / org / argeo / jcr / ui / explorer / model / SingleJcrNode.java

diff --git a/server/plugins/org.argeo.jcr.ui.explorer/src/main/java/org/argeo/jcr/ui/explorer/model/SingleJcrNode.java b/server/plugins/org.argeo.jcr.ui.explorer/src/main/java/org/argeo/jcr/ui/explorer/model/SingleJcrNode.java
new file mode 100644 (file)
index 0000000..03ac522
--- /dev/null
+++ b/server/plugins/org.argeo.jcr.ui.explorer/src/main/java/org/argeo/jcr/ui/explorer/model/SingleJcrNode.java
@@ -0,0 +1,103 @@
+package org.argeo.jcr.ui.explorer.model;
+
+import javax.jcr.Node;
+import javax.jcr.NodeIterator;
+import javax.jcr.RepositoryException;
+import javax.jcr.Workspace;
+
+import org.argeo.ArgeoException;
+import org.argeo.eclipse.ui.TreeParent;
+
+/**
+ * UI Tree component. Wraps a node of a JCR {@link Workspace}. It also keeps a
+ * reference to its parent node that can either be a {@link WorkspaceNode}, a
+ * {@link SingleJcrNode} or null if the node is "mounted" as the root of the UI
+ * tree.
+ */
+
+public class SingleJcrNode extends TreeParent implements UiNode {
+
+       private final Node node;
+       private String alias = null;
+
+       // keeps a local reference to the node's name to avoid exception when the
+       // session is lost
+       // private final String name;
+
+       /** Creates a new UiNode in the UI Tree */
+       public SingleJcrNode(TreeParent parent, Node node, String name) {
+               super(name);
+               setParent(parent);
+               this.node = node;
+       }
+
+       /**
+        * Creates a new UiNode in the UI Tree, keeping a reference to the alias of
+        * the corresponding repository in the current UI environment. It is useful
+        * to be able to mount nodes as roots of the UI tree.
+        */
+       public SingleJcrNode(TreeParent parent, Node node, String name, String alias) {
+               super(name);
+               setParent(parent);
+               this.node = node;
+               this.alias = alias;
+       }
+
+       /** returns the node wrapped by the current Ui object */
+       public Node getNode() {
+               return node;
+       }
+
+       /**
+        * Returns the alias corresponding to the repository abstraction that
+        * contains current node. If the current object is mounted as root of the UI
+        * tree, the alias is stored in the object. Otherwise, we must browse the
+        * tree backward to the RepositoryNode.
+        * 
+        * Alias is then cached in the current object so that next time it will be
+        * here.
+        */
+       public String getAlias() {
+               if (alias == null) {
+                       alias = ((UiNode) getParent()).getAlias();
+               }
+               return alias;
+       }
+
+       /**
+        * Override normal behaviour to initialize children only when first
+        * requested
+        */
+       @Override
+       public synchronized Object[] getChildren() {
+               if (isLoaded()) {
+                       return super.getChildren();
+               } else {
+                       // initialize current object
+                       try {
+                               NodeIterator ni = node.getNodes();
+                               while (ni.hasNext()) {
+                                       Node curNode = ni.nextNode();
+                                       addChild(new SingleJcrNode(this, curNode, curNode.getName()));
+                               }
+                               return super.getChildren();
+                       } catch (RepositoryException re) {
+                               throw new ArgeoException(
+                                               "Unexcpected error while initializing children SingleJcrNode",
+                                               re);
+                       }
+               }
+       }
+
+       @Override
+       public boolean hasChildren() {
+               try {
+                       return node.hasNodes();
+               } catch (RepositoryException re) {
+                       throw new ArgeoException(
+                                       "Unexpected error while checking children node existence",
+                                       re);
+               }
+       }
+
+}