org.gersteinlab.tyna.core.graph
Class Node

java.lang.Object
  org.gersteinlab.tyna.core.graph.Node

All Implemented Interfaces:

java.lang.Comparable, java.io.Serializable

public class Node

extends java.lang.Object

implements java.lang.Comparable, java.io.Serializable

	This class represents a node in a graph. Node ID is the only defined
	attribute. It has to be a non-null unique identifier. Other attributes
	such as node label (if not unique) and node color can be accessed
	through the attribute get-setters. Subclasses can be defined for node
	types that contain additional attributes, if that is more convenient
	than using the attribute get-setters.

	Edges are defined in graphs, the information is not stored in this
	class.

	The ID is to be assigned at object instantiation time only, and should
	not to be changed since it affects hashCode(), equals(), etc.

	Two nodes are the same if and only if they refer to the same object, or
	if they have the same non-null ID. hashCode() and equals() are defined
	in a way that both order-based structures (e.g. TreeSet) and hash-based
	structures (e.g. HashSet) can be used.
	

Version:

1.1 (January 14, 2006) Change History: 1.0 - Initial version 1.1 - Non-null ID becomes mandatory

Author:

Kevin Yuk-Lap Yip

See Also:

Serialized Form

Field Summary

protected java.util.Map	attrs The (possibly null) other attributes of the node.
protected java.lang.Object	id The ID of the node.

Constructor Summary

Node()
Default constructor: creates a node with no ID or attributes.

Node(java.lang.Object id, java.util.Map attrs)
Constructor: creates a node with an ID and/or attributes.

Method Summary

int	compareTo(java.lang.Object o)
boolean	equals(java.lang.Object o)
java.lang.Object	getAttr(java.lang.Object attrName) Get the (possibly null) value of an attribute of the node.
java.util.Map	getAttrs() Get the (possibly null) attribute map of the node.
java.lang.Object	getId() Get the ID of the node.
int	hashCode()
void	removeAttr(java.lang.Object attrName) Remove the value of an attribute from the node.
void	setAttr(java.lang.Object attrName, java.lang.Object attrVal) Set the value of an attribute of the node.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

id

protected java.lang.Object id

The ID of the node.

attrs

protected java.util.Map attrs

The (possibly null) other attributes of the node.

Constructor Detail

Node

public Node()

Default constructor: creates a node with no ID or attributes.

Node

public Node(java.lang.Object id,
            java.util.Map attrs)

Constructor: creates a node with an ID and/or attributes. Input null if not used. A copy of attrs, rather than the original object, is being stored.

Parameters:

id - The node ID

attrs - Node attributes

Method Detail

compareTo

public int compareTo(java.lang.Object o)

Specified by:

compareTo in interface java.lang.Comparable

Returns:

Determine by ID if present, otherwise by hashCode

See Also:

Comparable.compareTo(Object)

equals

public boolean equals(java.lang.Object o)

Returns:

true if and only if the input object refers to the same node as the current one (same non-null ID, or same object)

See Also:

Object.equals(Object)

hashCode

public int hashCode()

Returns:

java.lang.object.hashCode if id == null, the hash code of ID otherwise. Beware not to use a node as the ID of another node, which will lead to recursive definitions.

See Also:

Object.hashCode()

getId

public java.lang.Object getId()

Get the ID of the node.

Returns:

The node ID

getAttr

public java.lang.Object getAttr(java.lang.Object attrName)

Get the (possibly null) value of an attribute of the node.

Parameters:

attrName - The name of the attribute

Returns:

The value of the attribute

getAttrs

public java.util.Map getAttrs()

Get the (possibly null) attribute map of the node. A copy of the stored map is returned.

Returns:

The attribute map

setAttr

public void setAttr(java.lang.Object attrName,
                    java.lang.Object attrVal)

Set the value of an attribute of the node.

Parameters:

attrName - The name of the attribute

attrVal - The value of the attribute

removeAttr

public void removeAttr(java.lang.Object attrName)

Remove the value of an attribute from the node.

Parameters:

attrName - The name of the attribute

toString

public java.lang.String toString()