Class GraphScene<N,E>

java.lang.Object
org.netbeans.api.visual.widget.Widget
org.netbeans.api.visual.widget.Scene
org.netbeans.api.visual.model.ObjectScene
org.netbeans.api.visual.graph.GraphScene<N,E>
All Implemented Interfaces:
Accessible, org.openide.util.Lookup.Provider
Direct Known Subclasses:
GraphScene.StringGraph
public abstract class GraphScene<N,E> extends ObjectScene
This class holds and manages graph-oriented model.

In comparison with the GraphScene class, in this class the graph consists of nodes and edges. Each edge could be attach to a single source and target node.

The class is abstract and manages only data model and mapping with widgets. The graphics (widgets) has to be supplied by a developer by overriding the attachNodeWidget, attachEdgeWidget, attachEdgeSourceAnchor and attachEdgeTargetAnchor abstract methods.

This class is using generics and allows you to specify type representation for nodes and edges in the graph model. Example: 

 class MyGraph extends GraphScene<MyNode, MyEdge> { ... }
Since the type of nodes and edges could be the same, all node and edge instances has to be unique within the whole scene.

Node and Edge should not be a Widget. It should work properly but in that case the ObjectScene class is loosing its purpose because there is no need to manage a mapping of an instance to the same instance.

  • Constructor Details

    • GraphScene

      public GraphScene()
      Creates a graph scene.

  • Method Details

    • addNode

      public final Widget addNode(N node)
      Adds a node.
      Parameters:
      node - the node to be added; the node must not be null, must not be already in the model, must be unique in the model (means: there is no other node or edge in the model has is equal to this node) and must not be a Widget
      Returns:
      the widget that is created by attachNodeWidget; null if the node is non-visual

    • removeNode

      public final void removeNode(N node)
      Removes a node.
      Parameters:
      node - the node to be removed; the node must not be null and must be already in the model

    • removeNodeWithEdges

      public final void removeNodeWithEdges(N node)
      Removes a specified node with all edges that are attached to the node.
      Parameters:
      node - the node to be removed

    • getNodes

      public final Collection<N> getNodes()
      Returns a collection of all nodes registered in the graph model.
      Returns:
      the collection of all nodes registered in the graph model

    • addEdge

      public final Widget addEdge(E edge)
      Adds an edge.
      Parameters:
      edge - the edge to be added; the edge must not be null, must not be already in the model, must be unique in the model (means: there is no other node or edge in the model has is equal to this edge) and must not be a Widget
      Returns:
      the widget that is created by attachEdgeWidget; null if the edge is non-visual

    • removeEdge

      public final void removeEdge(E edge)
      Removes an edge and detaches it from its source and target nodes.
      Parameters:
      edge - the edge to be removed; the edge must not be null and must be already in the model

    • getEdges

      public final Collection<E> getEdges()
      Returns a collection of all edges registered in the graph model.
      Returns:
      the collection of all edges registered in the graph model

    • setEdgeSource

      public final void setEdgeSource(E edge, N sourceNode)
      Sets an edge source.
      Parameters:
      edge - the edge which source is going to be changed
      sourceNode - the source node; if null, then the edge source will be detached

    • setEdgeTarget

      public final void setEdgeTarget(E edge, N targetNode)
      Sets an edge target.
      Parameters:
      edge - the edge which target is going to be changed
      targetNode - the target node; if null, then the edge target will be detached

    • getEdgeSource

      public final N getEdgeSource(E edge)
      Returns an edge source.
      Parameters:
      edge - the edge
      Returns:
      the edge source; null, if edge does not have source attached

    • getEdgeTarget

      public final N getEdgeTarget(E edge)
      Returns an edge target.
      Parameters:
      edge - the edge
      Returns:
      the edge target; null, if edge does not have target attached

    • findNodeEdges

      public final Collection<E> findNodeEdges(N node, boolean allowOutputEdges, boolean allowInputEdges)
      Returns a collection of edges that are attached to a specified node.
      Parameters:
      node - the node which edges connections are searched for
      allowOutputEdges - if true, the output edges are included in the collection; if false, the output edges are not included
      allowInputEdges - if true, the input edges are included in the collection; if false, the input edges are not included
      Returns:
      the collection of edges

    • findEdgesBetween

      public final Collection<E> findEdgesBetween(N sourceNode, N targetNode)
      Returns a collection of edges that are between a specified source and target nodes.
      Parameters:
      sourceNode - the source node
      targetNode - the target node
      Returns:
      the collection of edges with the specified source and target nodes

    • isNode

      public boolean isNode(Object object)
      Checks whether an object is registered as a node in the graph model.
      Parameters:
      object - the object; must not be a Widget
      Returns:
      true, if the object is registered as a node

    • isEdge

      public boolean isEdge(Object object)
      Checks whether an object is registered as a edge in the graph model.
      Parameters:
      object - the object; must not be a Widget
      Returns:
      true, if the object is registered as a edge

    • notifyNodeAdded

      protected void notifyNodeAdded(N node, Widget widget)
      Called by the addNode method to notify that a node is added into the graph model.
      Parameters:
      node - the added node
      widget - the widget created by the attachNodeWidget method as a visual representation of the node

    • notifyEdgeAdded

      protected void notifyEdgeAdded(E edge, Widget widget)
      Called by the addEdge method to notify that an edge is added into the graph model.
      Parameters:
      edge - the added node
      widget - the widget created by the attachEdgeWidget method as a visual representation of the edge

    • detachNodeWidget

      protected void detachNodeWidget(N node, Widget widget)
      Called by the removeNode method to notify that a node is removed from the graph model. The default implementation removes the node widget from its parent widget.
      Parameters:
      node - the removed node
      widget - the removed node widget; null if the node is non-visual

    • detachEdgeWidget

      protected void detachEdgeWidget(E edge, Widget widget)
      Called by the removeEdge method to notify that an edge is removed from the graph model. The default implementation removes the edge widget from its parent widget.
      Parameters:
      edge - the removed edge
      widget - the removed edge widget; null if the edge is non-visual

    • attachNodeWidget

      protected abstract Widget attachNodeWidget(N node)
      Called by the addNode method before the node is registered to acquire a widget that is going to represent the node in the scene. The method is responsible for creating the widget, adding it into the scene and returning it from the method.
      Parameters:
      node - the node that is going to be added
      Returns:
      the widget representing the node; null, if the node is non-visual

    • attachEdgeWidget

      protected abstract Widget attachEdgeWidget(E edge)
      Called by the addEdge method before the edge is registered to acquire a widget that is going to represent the edge in the scene. The method is responsible for creating the widget, adding it into the scene and returning it from the method.
      Parameters:
      edge - the edge that is going to be added
      Returns:
      the widget representing the edge; null, if the edge is non-visual

    • attachEdgeSourceAnchor

      protected abstract void attachEdgeSourceAnchor(E edge, N oldSourceNode, N sourceNode)
      Called by the setEdgeSource method to notify about the changing the edge source in the graph model. The method is responsible for attaching a new source node to the edge in the visual representation.

      Usually it is implemented as: 

       Widget sourceNodeWidget = findWidget (sourceNode);
 Anchor sourceAnchor = AnchorFactory.createRectangularAnchor (sourceNodeWidget)
 ConnectionWidget edgeWidget = (ConnectionWidget) findWidget (edge);
 edgeWidget.setSourceAnchor (sourceAnchor);
      Parameters:
      edge - the edge which source is changed in graph model
      oldSourceNode - the old source node
      sourceNode - the new source node

    • attachEdgeTargetAnchor

      protected abstract void attachEdgeTargetAnchor(E edge, N oldTargetNode, N targetNode)
      Called by the setEdgeTarget method to notify about the changing the edge target in the graph model. The method is responsible for attaching a new target node to the edge in the visual representation.

      Usually it is implemented as: 

       Widget targetNodeWidget = findWidget (targetNode);
 Anchor targetAnchor = AnchorFactory.createRectangularAnchor (targetNodeWidget)
 ConnectionWidget edgeWidget = (ConnectionWidget) findWidget (edge);
 edgeWidget.setTargetAnchor (targetAnchor);
      Parameters:
      edge - the edge which target is changed in graph model
      oldTargetNode - the old target node
      targetNode - the new target node