Similar to LayoutWithoutAView, but demonstrates the use of node and edge grouping in combination with the layout algorithms that are capable of interpreting these sophisticated features. This too can be achieved without the classes that are only present in the yFiles Viewer distribution.

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 **
 ** This file is part of yFiles-2.6. 
 ** 
 ** yWorks proprietary/confidential. Use is subject to license terms.
 **
 ** Redistribution of this file or of an unauthorized byte-code version
 ** of this file is strictly forbidden.
 **
 ** Copyright (c) 2000-2008 by yWorks GmbH, Vor dem Kreuzberg 28, 
 ** 72070 Tuebingen, Germany. All rights reserved.
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 ***************************************************************************/

package demo.layout;

import y.base.Edge;
import y.base.EdgeMap;
import y.base.Node;
import y.base.NodeMap;

import y.layout.BufferedLayouter;
import y.layout.DefaultLayoutGraph;
import y.layout.PortConstraintKeys;
import y.layout.grouping.Grouping;
import y.layout.hierarchic.HierarchicGroupLayouter;

import y.util.D;

/**
 * This class shows how to use layout and grouping algorithms without using classes 
 * that are only present in the yFiles Viewer Distribution. Therefore this demo
 * only outputs the calculated coordinates of the graph layout to the console
 * and displays it inside a simple preview panel.
 * <br>
 * In this demo HierarchicGroupLayouter is used to layout a small graph. 
 */
public class GroupingLayoutWithoutAView
{
  
  /**
   * Launcher
   */
  public static void main(String[] args)
  {
    GroupingLayoutWithoutAView lwv = new GroupingLayoutWithoutAView();
    lwv.doit();
  }

  /**
   * Creates a small graph and applies a hierarchic group layout to it.
   * <p>
   * The output of the calculated coordinates will be displayed in the
   * console.
   */ 
  public void doit()
  {
    DefaultLayoutGraph graph = new DefaultLayoutGraph();
    
    //construct graph. assign sizes to nodes
    Node v1 = graph.createNode();
    graph.setSize(v1,30,30);
    Node v2 = graph.createNode();
    graph.setSize(v2,30,30);
    Node v3 = graph.createNode();
    graph.setSize(v3,30,30);
    Node v4 = graph.createNode();
    graph.setSize(v4,30,30);
    
    Node groupNode = graph.createNode();
    graph.setSize(groupNode, 100,100);
    
    Edge e1 = graph.createEdge(v1,v2);
    Edge e2 = graph.createEdge(v4, groupNode);
    Edge e3 = graph.createEdge(v1,v3);
    Edge e4 = graph.createEdge(v1, v1);
    Edge e5 = graph.createEdge(v2, groupNode);
    Edge e6 = graph.createEdge(groupNode, v2);
 
    //optionally setup some edge groups
    EdgeMap spg = graph.createEdgeMap();
    EdgeMap tpg = graph.createEdgeMap();
    
    graph.addDataProvider(PortConstraintKeys.SOURCE_GROUPID_KEY, spg);
    graph.addDataProvider(PortConstraintKeys.TARGET_GROUPID_KEY, tpg);
    
    spg.set(e1, "SGroup1");
    spg.set(e3, "SGroup1");
    tpg.set(e1, "TGroup1");
    tpg.set(e3, "TGroup1");

    //optionally setup the node grouping
    NodeMap nodeId = graph.createNodeMap();
    NodeMap parentNodeId = graph.createNodeMap();
    NodeMap groupKey = graph.createNodeMap();
    
    graph.addDataProvider(Grouping.NODE_ID_DPKEY, nodeId);
    graph.addDataProvider(Grouping.PARENT_NODE_ID_DPKEY, parentNodeId);
    graph.addDataProvider(Grouping.GROUP_DPKEY, groupKey);
    
    //mark a node as a group node
    groupKey.setBool(groupNode, true);
    
    // add ids for each node
    nodeId.set(v1, "v1");
    nodeId.set(v2, "v2");
    nodeId.set(v3, "v3");
    nodeId.set(v4, "v4");
    nodeId.set(groupNode, "groupNode");
    
    // set the parent for each grouped node
    parentNodeId.set(v2, "groupNode");
    parentNodeId.set(v3, "groupNode");
    
    HierarchicGroupLayouter layouter = new HierarchicGroupLayouter();
    
    layouter.setMinimalLayerDistance(0.0d);
    layouter.setMinimalEdgeDistance(10.0d);
  
    new BufferedLayouter(layouter).doLayout(graph);
    
    //display result
    LayoutPreviewPanel lpp = new LayoutPreviewPanel(graph);
    lpp.createFrame("Hierarchical Group Layout").setVisible(true);

    D.bug("\n\nGRAPH LAID OUT USING HIERACHIC GROUP LAYOUT");
    D.bug("v1 center position = " + graph.getCenter(v1));
    D.bug("v2 center position = " + graph.getCenter(v2));
    D.bug("v3 center position = " + graph.getCenter(v3));
    D.bug("v4 center position = " + graph.getCenter(v4));
    D.bug("group center position = " + graph.getCenter(groupNode));
    D.bug("group size = " + graph.getSize(groupNode));
    D.bug("e1 path = " + graph.getPath(e1));
    D.bug("e2 path = " + graph.getPath(e2));
    D.bug("e3 path = " + graph.getPath(e3));
    D.bug("e4 path = " + graph.getPath(e4));
    D.bug("e5 path = " + graph.getPath(e5));
    D.bug("e6 path = " + graph.getPath(e4));
  }
}