--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/org.eclipse.draw2d/src/org/eclipse/draw2d/graph/Subgraph.d	Sat Mar 14 18:23:29 2009 +0100
@@ -0,0 +1,122 @@
+/*******************************************************************************
+ * Copyright (c) 2003, 2005 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ * Port to the D programming language:
+ *     Frank Benoit <benoit@tionex.de>
+ *******************************************************************************/
+module org.eclipse.draw2d.graph.Subgraph;
+
+import java.lang.all;
+
+import org.eclipse.draw2d.geometry.Insets;
+import org.eclipse.draw2d.graph.Node;
+import org.eclipse.draw2d.graph.NodeList;
+
+
+/**
+ * A Node which may contain other nodes.  A Subgraph is a compound or container node.  It
+ * may have incoming and outgoing edges just like a node.  Subgraphs are used in {@link
+ * CompoundDirectedGraph}s.  A proper layout of a compound graph ensures that all of a
+ * subgraph's children are placed inside its rectangular region.  Nodes which do not
+ * belong to the subgraph must be placed outside that region.
+ * <P>
+ * A Subgraph may contain another Subgraph.
+ * <P>
+ * A Subgraph has additional geometric properties which describe the containing box.  They
+ * are:
+ * <UL>
+ *   <LI>{@link #insets} - the size of the subgraph's border.  A subgraph is typically
+ *   rendered as a thin rectangular box.  Sometimes this box is labeled or decorated.  The
+ *   insets can be used to reserve space for this purpose.
+ *   <LI>{@link #innerPadding} - the amount of empty space that must be preserved just
+ *   inside the subgraph's border.  This is the minimum space between the border, and the
+ *   children node's contained inside the subgraph.
+ * </UL>
+ *
+ * @author hudsonr
+ * @since 2.1.2
+ */
+public class Subgraph : Node {
+
+/**
+ * The children of this subgraph. Nodes may not belong to more than one subgraph.
+ */
+public NodeList members;
+
+Node head;
+Node tail;
+Node left;
+Node right;
+int nestingTreeMin;
+
+/**
+ * The space required for this subgraph's border.  The default value is undefined.
+ */
+public Insets insets;
+
+/**
+ * The minimum space between this subgraph's border and it's children.
+ */
+public Insets innerPadding;
+
+private static Insets NO_INSETS_;
+private static Insets NO_INSETS(){
+    if( NO_INSETS_ is null ){
+        synchronized( Subgraph.classinfo ){
+            if( NO_INSETS_ is null ){
+                NO_INSETS_ = new Insets();
+            }
+        }
+    }
+    assert( NO_INSETS_ );
+    return NO_INSETS_;
+}
+
+/**
+ * Constructs a new subgraph with the given data object.
+ * @see Node#Node(Object)
+ * @param data an arbitrary data object
+ */
+public this(Object data) {
+    this(data, null);
+}
+
+/**
+ * Constructs a new subgraph with the given data object and parent subgraph.
+ * @see Node#Node(Object, Subgraph)
+ * @param data an arbitrary data object
+ * @param parent the parent
+ */
+public this(Object data, Subgraph parent) {
+    super(data, parent);
+    innerPadding = NO_INSETS;
+    members = new NodeList();
+    insets = new Insets(1);
+}
+
+/**
+ * Adds the given node to this subgraph.
+ * @param n the node to add
+ */
+public void addMember(Node n) {
+    members.add(n);
+}
+
+/**
+ * Returns <code>true</code> if the given node is contained inside the branch represented
+ * by this subgraph.
+ * @param n the node in question
+ * @return <code>true</code> if nested
+ */
+bool isNested(Node n) {
+    return n.nestingIndex >= nestingTreeMin
+        && n.nestingIndex <= nestingIndex;
+}
+
+}