com.lexonics.edsel
Class Node

java.lang.Object
  com.lexonics.edsel.Node

public final class Node

extends Object

An Edsel node. A Node has a name and an attribute set. The name is a valid Edsel identifier; that is, it is a non-null, non-empty String that contains no characters other than upper- and lowercase ASCII letters, digits, and hyphens. Names beginning with hyphens are reserved. By convention, node names are concatenations of words with only the first character of each word uppercase. The attribute set is a non-null Set of Attributes; no two Attributes in the attribute set have equal names. Nodes are immutable.

Field Summary

static Node	Edge The predefined structure Node with name -Edge.
static Node	MultiAttribute The predefined structure Node with name -MultiAttribute.
static Node	MultiEdge The predefined structure Node with name -MultiEdge.
static Node	Structure The predefined structure Node with name -Structure.

Constructor Summary

Node(String name)
Construct a Node with a given name and an empty attribute set.

Node(String name, Set attributeSet)
Construct a Node with a given name and attribute set.

Method Summary

Attribute	attribute(String name) Return the Attribute in this Node with a given name, or null if none.
Set	attributeSet() Return a shallow copy of the attribute set of this Node.
boolean	equals(Object o) Compare a given object with this Node for equality.
int	hashCode() Return the hash code value for this Node.
String	name() Return the name of this Node.
static Node	predefinedStructureNode(String name) Return the predefined structure node with a given name, or null if none.
String	toString() Return a string representation of this Node.

Methods inherited from class java.lang.Object

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

Field Detail

Structure

public static final Node Structure

The predefined structure Node with name -Structure.

MultiAttribute

public static final Node MultiAttribute

The predefined structure Node with name -MultiAttribute.

Edge

public static final Node Edge

The predefined structure Node with name -Edge.

MultiEdge

public static final Node MultiEdge

The predefined structure Node with name -MultiEdge.

Constructor Detail

Node

public Node(String name)

Construct a Node with a given name and an empty attribute set.

Parameters:

name - The name of the Node. Must be a valid Edsel identifier.

Throws:

IllegalArgumentException - The name is not a valid Edsel identifier.

Node

public Node(String name,
            Set attributeSet)

Construct a Node with a given name and attribute set.

Parameters:

name - The name of the Node. Must be a valid Edsel identifier.

attributeSet - The attribute set of the Node. Must be a non-null Set of Attributes, no two of which have equal names. This set is copied by a shallow copy, to guarantee Node immutability.

Throws:

IllegalArgumentException - The name is not a valid Edsel identifier, the attribute set is null, an element of the attribute set is not an Attribute, or two Attributes in the attribute set have equal names.

Method Detail

attribute

public Attribute attribute(String name)

Return the Attribute in this Node with a given name, or null if none.

Parameters:

name - The name.

Returns:

The Attribute in this Node with the given name, or null if none.

attributeSet

public Set attributeSet()

Return a shallow copy of the attribute set of this Node.

Returns:

A shallow copy of the attribute set of this Node.

equals

public boolean equals(Object o)

Compare a given object with this Node for equality. Return true if the given object is also a Node, and the two Nodes have equal names and attribute sets.

Parameters:

o - The object.

Returns:

true if the object is equal to this Node.

hashCode

public int hashCode()

Return the hash code value for this Node. The hash code of a Node is defined to be the sum of the hash codes of its name and attribute set.

Returns:

The hash code value for this Node.

name

public String name()

Return the name of this Node.

Returns:

The name of this Node.

predefinedStructureNode

public static Node predefinedStructureNode(String name)

Return the predefined structure node with a given name, or null if none.

Parameters:

name - The name.

Returns:

The predefined structure node with the given name, or null if none.

toString

public String toString()

Return a string representation of this Node.

Returns:

The string representation. Any backslash or single quote in the value of an Attribute in the attribute set is escaped by a backslash.