com.yworks.yfiles.layout.hierarchic

Class TopologicalLayerer

java.lang.Object

com.yworks.yfiles.layout.hierarchic.TopologicalLayerer

All Implemented Interfaces:

ILayerer

public class TopologicalLayerer
extends Object
implements ILayerer

This class implements the layering phase of the HierarchicLayout (i.e., assignment of the nodes to layers).

It uses topological sorting to assign layers to the nodes.

Constructor Summary

Constructors

Constructor and Description
TopologicalLayerer() Creates a new instance of TopologicalLayerer with default settings.

Method Summary

Modifier and Type	Method and Description
void	assignLayers(LayoutGraph graph, ILayers layers, ILayoutDataProvider ldp) Assigns all nodes of the graph to layers and adds them to the ILayers instance.
int	assignNodeLayer(LayoutGraph graph, INodeMap layerID, EdgeList reversedEdges) This method assigns the nodes in the graph to layers.
RankingPolicy	getRankingPolicy() Gets the (re-)ranking policy used by this TopologicalLayerer instance.
void	setRankingPolicy(RankingPolicy value) Sets the (re-)ranking policy used by this TopologicalLayerer instance.

Methods inherited from class java.lang.Object

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

Constructor Detail

TopologicalLayerer

public TopologicalLayerer()

Creates a new instance of TopologicalLayerer with default settings.

Method Detail

assignLayers

public void assignLayers(LayoutGraph graph,
                         ILayers layers,
                         ILayoutDataProvider ldp)

Assigns all nodes of the graph to layers and adds them to the ILayers instance.

Specified by:

assignLayers in interface ILayerer

Parameters:

graph - the input graph

layers - the ILayers instance that will be filled with the results of the calculation

ldp - the ILayoutDataProvider used for querying information about the nodes and edges

See Also:

ILayers.insert(com.yworks.yfiles.layout.hierarchic.LayerType, int), ILayer.add(com.yworks.yfiles.algorithms.Node)

assignNodeLayer

public int assignNodeLayer(LayoutGraph graph,
                           INodeMap layerID,
                           EdgeList reversedEdges)

This method assigns the nodes in the graph to layers.

Postcondition:

For all (v,w) in E: layer(v) < layer(w)

Parameters:

graph - the given graph

layerID - the INodeMap that will be filled by the layout algorithm and returns the zero-based index of the layer to which each node belongs

reversedEdges - an EdgeList containing the edges which had been reversed

Returns:

the number of layers

getRankingPolicy

public RankingPolicy getRankingPolicy()

Gets the (re-)ranking policy used by this TopologicalLayerer instance.

Throws:

IllegalArgumentException - if an unknown ranking policy is given

Default Value:

The default value is RankingPolicy.NO_RERANKING

Returns:

one of the predefined ranking policies

See Also:

setRankingPolicy(RankingPolicy)

setRankingPolicy

public void setRankingPolicy(RankingPolicy value)

Sets the (re-)ranking policy used by this TopologicalLayerer instance.

Throws:

IllegalArgumentException - if an unknown ranking policy is given

Default Value:

The default value is RankingPolicy.NO_RERANKING

Parameters:

value - one of the predefined ranking policies

See Also:

getRankingPolicy()