uk.ac.starlink.util

Class StarEntityResolver

java.lang.Object

uk.ac.starlink.util.StarEntityResolver

All Implemented Interfaces:

EntityResolver

public class StarEntityResolver
extends Object
implements EntityResolver

Provides specialised XML entity resolution. This resolver knows about some entities which starjava applications are likely to want to retrieve; it keeps copies of them so that no network connection is required for them.

Use getInstance() to obtain an instance of this class without a parent.

Author:

Mark Taylor (Starlink)

Constructor Summary

Constructors

Constructor and Description
StarEntityResolver(EntityResolver parent) Constructs a resolver which will resolve entities this class knows about, and for those it doesn't it will defer resolution to a supplied parent resolver.

Method Summary

Modifier and Type	Method and Description
static StarEntityResolver	getInstance() Returns the sole instance of this class.
protected String	getLocalResource(String publicId, String systemId) Returns a resource name locating the entity referenced by a given public/system ID pair.
InputSource	resolveEntity(String publicId, String systemId) Resolves an entity if it is one of the ones that we keep on hand.

Methods inherited from class java.lang.Object

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

Constructor Detail

StarEntityResolver

public StarEntityResolver(EntityResolver parent)

Constructs a resolver which will resolve entities this class knows about, and for those it doesn't it will defer resolution to a supplied parent resolver.

Parameters:

parent - fallback resolver (may be null)

Method Detail

getInstance

public static StarEntityResolver getInstance()

Returns the sole instance of this class.

Returns:

StarEntityResolver instance

resolveEntity

public InputSource resolveEntity(String publicId,
                                 String systemId)
                          throws SAXException,
                                 IOException

Resolves an entity if it is one of the ones that we keep on hand.

Specified by:

resolveEntity in interface EntityResolver

Throws:

SAXException

IOException

getLocalResource

protected String getLocalResource(String publicId,
                                  String systemId)

Returns a resource name locating the entity referenced by a given public/system ID pair. If there is a local copy of this entity, its path relative to this class is returned, otherwise null is returned.

Parameters:

systemId - the entity's system ID

publicId - the entity's public ID

Returns:

path to the resource, or null if it is unknown