com.hp.hpl.jena.enhanced
Class EnhNode

java.lang.Object
  com.hp.hpl.jena.enhanced.Polymorphic<RDFNode>
      com.hp.hpl.jena.enhanced.EnhNode

All Implemented Interfaces:

FrontsNode

public class EnhNode
extends Polymorphic<RDFNode>
implements FrontsNode

A specialisation of Polymorphic that models an extended node in a an extended graph. An extended node wraps a normal node, and adds additional convenience access or user affordances, though the state remains in the graph itself.

Author:

Jeremy Carroll (original code)
Chris Dollin (original code)
Ian Dickinson (refactoring and commentage)

Constructor Summary

EnhNode(Node n, EnhGraph g)

Method Summary

<T extends RDFNode> T	as(java.lang.Class<T> t) allow subclasses to implement RDFNode & its subinterface
Node	asNode() Answer the graph node that this enhanced node wraps
<X extends RDFNode> boolean	canAs(java.lang.Class<X> t) API-level method for polymorphic testing
boolean	equals(java.lang.Object o) An enhanced node is equal to another enhanced node n iff the underlying nodes are equal.
EnhGraph	getGraph() Answer the graph containing this node
int	hashCode() The hash code of an enhanced node is defined to be the same as the underlying node.
boolean	isAnon() An enhanced node is Anon[ymous] iff its underlying node is Blank.
boolean	isLiteral() An enhanced node is Literal iff its underlying node is too.
boolean	isResource() An enhanced node is a resource if it's node is a URI node or a blank node.
boolean	isURIResource() An enhanced node is a URI resource iff its underlying node is too.
boolean	isValid() answer true iff this enhanced node is still underpinned in the graph by triples appropriate to its type.
<X extends RDFNode> X	viewAs(java.lang.Class<X> t) Answer a facet of this node, where that facet is denoted by the given type.

Methods inherited from class com.hp.hpl.jena.enhanced.Polymorphic

addView, supports

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

EnhNode

public EnhNode(Node n,
               EnhGraph g)

Method Detail

asNode

public Node asNode()

Answer the graph node that this enhanced node wraps

Specified by:

asNode in interface FrontsNode

Returns:

A plain node

getGraph

public EnhGraph getGraph()

Answer the graph containing this node

Returns:

An enhanced graph

isAnon

public final boolean isAnon()

An enhanced node is Anon[ymous] iff its underlying node is Blank.

isLiteral

public final boolean isLiteral()

An enhanced node is Literal iff its underlying node is too.

isURIResource

public final boolean isURIResource()

An enhanced node is a URI resource iff its underlying node is too.

isResource

public final boolean isResource()

An enhanced node is a resource if it's node is a URI node or a blank node.

viewAs

public <X extends RDFNode> X viewAs(java.lang.Class<X> t)

Answer a facet of this node, where that facet is denoted by the given type.

Parameters:

t - A type denoting the desired facet of the underlying node

Returns:

An enhanced nodet that corresponds to t; this may be this Java object, or a different object.

as

public <T extends RDFNode> T as(java.lang.Class<T> t)

allow subclasses to implement RDFNode & its subinterface

canAs

public <X extends RDFNode> boolean canAs(java.lang.Class<X> t)

API-level method for polymorphic testing

hashCode

public final int hashCode()

The hash code of an enhanced node is defined to be the same as the underlying node.

Overrides:

hashCode in class java.lang.Object

Returns:

The hashcode as an int

equals

public final boolean equals(java.lang.Object o)

An enhanced node is equal to another enhanced node n iff the underlying nodes are equal. We generalise to allow the other object to be any class implementing asNode, because we allow other implemementations of Resource than EnhNodes, at least in principle. This is deemed to be a complete and correct interpretation of enhanced node equality, which is why this method has been marked final.

Specified by:

equals in class Polymorphic<RDFNode>

Parameters:

o - An object to test for equality with this node

Returns:

True if o is equal to this node.

isValid

public boolean isValid()

Description copied from class: Polymorphic

answer true iff this enhanced node is still underpinned in the graph by triples appropriate to its type.

Specified by:

isValid in class Polymorphic<RDFNode>