y.base
Class GraphEvent

java.lang.Object
  java.util.EventObject
      y.base.GraphEvent

All Implemented Interfaces:

java.io.Serializable

public class GraphEvent
extends java.util.EventObject

An event which indicates that a graph structure change occurred. This low-level event is generated by a graph when its structure changes. The event is passed to every GraphListener object that registered to receive such events using the graph's addGraphListener method.

The object that implements the GraphListener interface gets this GraphEvent when the event occurs.

Each GraphEvent has a type that signals what kind of change occurred in the graph and a data object that is the object (either node or edge) that was involved in the structural change of the graph, e.g., the node that has been created or the edge that has been reversed.

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Serialized Form

Field Summary

static byte	EDGE_CREATION Type constant that identifies an event that gets fired immediately after an edge has been created.
static byte	EDGE_REINSERTION Type constant that identifies an event that gets fired immediately after an edge has been reinserted into the graph.
static byte	NODE_CREATION Type constant that identifies an event that gets fired immediately after a node has been created.
static byte	NODE_REINSERTION Type constant that identifies an event that gets fired immediately after a node has been reinserted into the graph.
static byte	POST_EDGE_CHANGE Type constant that identifies an event that gets fired immediately after the end points of an edge have been changed.
static byte	POST_EDGE_REMOVAL Type constant that identifies an event that gets fired immediately after an edge has been removed from the graph.
static byte	POST_EVENT Type constant that signals the end of a some logically coherent event sequence.
static byte	POST_NODE_REMOVAL Type constant that identifies an event that gets fired immediately after a node has been removed from the graph.
static byte	PRE_EDGE_CHANGE Type constant that identifies an event that gets fired immediately before the end points of an edge will be changed.
static byte	PRE_EDGE_REMOVAL Type constant that identifies an event that gets fired immediately before an edge will be removed from the graph.
static byte	PRE_EVENT Type constant that signals the start of a some logically coherent event sequence.
static byte	PRE_NODE_REMOVAL Type constant that identifies an event that gets fired immediately before a node will be removed from the graph.
static byte	SUBGRAPH_INSERTION Type constant that identifies an event that gets fired after a subgraph of a graph G has been moved to the emitting graph.
static byte	SUBGRAPH_REMOVAL Type constant that identifies an event that gets fired after a subgraph of the emitting graph has been moved to a graph G.

Fields inherited from class java.util.EventObject

source

Constructor Summary

GraphEvent(Graph source, byte type, java.lang.Object data)
Creates a new GraphEvent instance with given type and data.

Method Summary

java.lang.Object	getData() Returns the data object associated with this graph event.
Graph	getGraph() Returns the graph that is the emitter of this event.
byte	getType() Returns the type of this GraphEvent.
java.lang.String	toString() Returns a String representation of this GraphEvent object's type.

Methods inherited from class java.util.EventObject

getSource

Methods inherited from class java.lang.Object

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

Field Detail

NODE_CREATION

public static final byte NODE_CREATION

Type constant that identifies an event that gets fired immediately after a node has been created. The data of the event is the newly created node.

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Constant Field Values

EDGE_CREATION

public static final byte EDGE_CREATION

Type constant that identifies an event that gets fired immediately after an edge has been created. The data of the event is the newly created edge.

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Constant Field Values

PRE_NODE_REMOVAL

public static final byte PRE_NODE_REMOVAL

Type constant that identifies an event that gets fired immediately before a node will be removed from the graph. The data of the event is the node to be removed.

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Constant Field Values

POST_NODE_REMOVAL

public static final byte POST_NODE_REMOVAL

Type constant that identifies an event that gets fired immediately after a node has been removed from the graph. The data of the event is the removed node.

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Constant Field Values

PRE_EDGE_REMOVAL

public static final byte PRE_EDGE_REMOVAL

Type constant that identifies an event that gets fired immediately before an edge will be removed from the graph. The data of the event is the edge to be removed.

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Constant Field Values

POST_EDGE_REMOVAL

public static final byte POST_EDGE_REMOVAL

Type constant that identifies an event that gets fired immediately after an edge has been removed from the graph. The data of the event is the removed edge.

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Constant Field Values

NODE_REINSERTION

public static final byte NODE_REINSERTION

Type constant that identifies an event that gets fired immediately after a node has been reinserted into the graph. The data of the event is the reinserted node.

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Constant Field Values

EDGE_REINSERTION

public static final byte EDGE_REINSERTION

Type constant that identifies an event that gets fired immediately after an edge has been reinserted into the graph. The data of the event is the reinserted edge.

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Constant Field Values

PRE_EDGE_CHANGE

public static final byte PRE_EDGE_CHANGE

Type constant that identifies an event that gets fired immediately before the end points of an edge will be changed. The data of the event is the edge to be redefined.

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Constant Field Values

POST_EDGE_CHANGE

public static final byte POST_EDGE_CHANGE

Type constant that identifies an event that gets fired immediately after the end points of an edge have been changed. The data of the event is the redefined edge.

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Constant Field Values

SUBGRAPH_INSERTION

public static final byte SUBGRAPH_INSERTION

Type constant that identifies an event that gets fired after a subgraph of a graph G has been moved to the emitting graph. The data of the event is a NodeList containing the nodes that induce the moved subgraph.

This event gets fired just after the SUBGRAPH_REMOVAL event got fired on the subgraph's original graph G. Note that at the time the event gets fired, the nodes from the node list are already part of the emitting graph.

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Constant Field Values

SUBGRAPH_REMOVAL

public static final byte SUBGRAPH_REMOVAL

Type constant that identifies an event that gets fired after a subgraph of the emitting graph has been moved to a graph G. The data of the event is a NodeList containing the nodes that induce the moved subgraph.

This event gets fired just before the SUBGRAPH_INSERTION event will be fired on the subgraph's new graph G. Note that at the time the event gets fired, the nodes from the node list are already part of graph G.

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Constant Field Values

PRE_EVENT

public static final byte PRE_EVENT

Type constant that signals the start of a some logically coherent event sequence. If specified, the data of this event is its ID.

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Constant Field Values

POST_EVENT

public static final byte POST_EVENT

Type constant that signals the end of a some logically coherent event sequence. If specified, the data of this event is its ID.

See Also:

Constant Field Values

Constructor Detail

GraphEvent

public GraphEvent(Graph source,
                  byte type,
                  java.lang.Object data)

Creates a new GraphEvent instance with given type and data.

Method Detail

getType

public byte getType()

Returns the type of this GraphEvent. It can be either of the type constants defined in this class.

getData

public java.lang.Object getData()

Returns the data object associated with this graph event. For a "Node"-associated event, it returns an object of type y.base.Node. For an "Edge"-associated event, it returns an object of type y.base.Edge. To check the type of event, see the method getType()

getGraph

public Graph getGraph()

Returns the graph that is the emitter of this event.

toString

public java.lang.String toString()

Returns a String representation of this GraphEvent object's type.

Overrides:

toString in class java.util.EventObject