y.layout.router
Class GroupNodeRouterStage

java.lang.Object
  y.layout.AbstractLayoutStage
      y.layout.router.GroupNodeRouterStage

All Implemented Interfaces:

Layouter, LayoutStage

public class GroupNodeRouterStage
extends AbstractLayoutStage

GroupNodeRouterStage adds support for hierarchically grouped graphs to OrthogonalEdgeRouter.

Concept

Group nodes as well as normal nodes are considered as obstacles for OrthogonalEdgeRouter. Thus, they have to be avoided during the routing of edges which is counterproductive if one endpoint of an edge is contained in a group node.

To avoid such difficulties, this stage temporarily removes group nodes and inserts some placeholders instead. Thus, the obstacles are not present for the core layout algorithm but the information about the bounds of the group nodes is maintained. Also, edges can connect to group nodes. After invoking the core layout algorithm, the group nodes are reinserted.

Hierarchically grouped graph

GroupNodeRouterStage will not have an effect with edge routing algorithms other than OrthogonalEdgeRouter.

See Also:

OrthogonalEdgeRouter, Grouping, GroupingKeys

Field Summary

Fields inherited from interface y.layout.Layouter

EDGE_ID_DPKEY, NODE_ID_DPKEY, NODE_TYPE_DPKEY, SELECTED_EDGES, SELECTED_NODES

Constructor Summary

GroupNodeRouterStage()
Creates a new instance of GroupNodeRouterStage.

GroupNodeRouterStage(Layouter coreLayouter)
Creates a new instance of GroupNodeRouterStage using the given core layout algorithm.

Method Summary

boolean	canLayout(LayoutGraph graph) Accepts all graphs that are accepted by the core layout algorithm.
void	doLayout(LayoutGraph graph) Handles hierarchically grouped graphs for the core layout algorithm.

Methods inherited from class y.layout.AbstractLayoutStage

canLayoutCore, doLayoutCore, getCoreLayouter, setCoreLayouter

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GroupNodeRouterStage

public GroupNodeRouterStage()

Creates a new instance of GroupNodeRouterStage.

GroupNodeRouterStage will not have an effect with edge routing algorithms other than OrthogonalEdgeRouter. An according core layout algorithm must be set.

GroupNodeRouterStage

public GroupNodeRouterStage(Layouter coreLayouter)

Creates a new instance of GroupNodeRouterStage using the given core layout algorithm.

GroupNodeRouterStage provides an optimization step for OrthogonalEdgeRouter and will not work with other edge routing algorithms.

Parameters:

coreLayouter - the core layout algorithm

Method Detail

canLayout

public boolean canLayout(LayoutGraph graph)

Accepts all graphs that are accepted by the core layout algorithm.

Parameters:

graph - the input graph

Returns:

true if the core layout algorithm can handle the given graph, false otherwise

See Also:

Layouter.doLayout(LayoutGraph)

doLayout

public void doLayout(LayoutGraph graph)

Handles hierarchically grouped graphs for the core layout algorithm.

Precondition:

The core layout algorithm must be an instance of OrthogonalEdgeRouter or at least must have such an instance in its layout pipeline.

Parameters:

graph - the input graph

See Also:

Layouter.canLayout(LayoutGraph)