org.apache.xerces.util
Class XMLCatalogResolver

java.lang.Object
  org.apache.xerces.util.XMLCatalogResolver

All Implemented Interfaces:

XMLEntityResolver, LSResourceResolver, EntityResolver, EntityResolver2

public class XMLCatalogResolver
extends java.lang.Object
implements XMLEntityResolver, EntityResolver2, LSResourceResolver

The catalog resolver handles the resolution of external identifiers and URI references through XML catalogs. This component supports XML catalogs defined by the OASIS XML Catalogs Specification. It encapsulates the XML Commons resolver. An instance of this class may be registered on the parser as a SAX entity resolver, as a DOM LSResourceResolver or as an XNI entity resolver by setting the property (http://apache.org/xml/properties/internal/entity-resolver).

It is intended that this class may be used standalone to perform catalog resolution outside of a parsing context. It may be shared between several parsers and the application.

Version:

$Id: XMLCatalogResolver.java 570138 2007-08-27 14:21:51Z mrglavas $

Author:

Michael Glavassevich, IBM

Constructor Summary

XMLCatalogResolver()
Constructs a catalog resolver with a default configuration.

XMLCatalogResolver(java.lang.String[] catalogs)
Constructs a catalog resolver with the given list of entry files.

XMLCatalogResolver(java.lang.String[] catalogs, boolean preferPublic)
Constructs a catalog resolver with the given list of entry files and the preference for whether system or public matches are preferred.

Method Summary

void	clear() Forces the cache of catalog mappings to be cleared.
java.lang.String[]	getCatalogList() Returns the initial list of catalog entry files.
InputSource	getExternalSubset(java.lang.String name, java.lang.String baseURI) Locates an external subset for documents which do not explicitly provide one.
boolean	getPreferPublic() Returns the preference for whether system or public matches are preferred.
boolean	getUseLiteralSystemId() Returns the preference for whether the literal system identifier should be used when resolving system identifiers when both it and the expanded system identifier are available.
InputSource	resolveEntity(java.lang.String publicId, java.lang.String systemId) Resolves an external entity.
InputSource	resolveEntity(java.lang.String name, java.lang.String publicId, java.lang.String baseURI, java.lang.String systemId) Resolves an external entity.
XMLInputSource	resolveEntity(XMLResourceIdentifier resourceIdentifier) Resolves an external entity.
java.lang.String	resolveIdentifier(XMLResourceIdentifier resourceIdentifier) Resolves an identifier using the catalog.
java.lang.String	resolvePublic(java.lang.String publicId, java.lang.String systemId) Returns the URI mapping in the catalog for the given external identifier or null if no mapping exists.
LSInput	resolveResource(java.lang.String type, java.lang.String namespaceURI, java.lang.String publicId, java.lang.String systemId, java.lang.String baseURI) Resolves a resource using the catalog.
java.lang.String	resolveSystem(java.lang.String systemId) Returns the URI mapping in the catalog for the given external identifier or null if no mapping exists.
java.lang.String	resolveURI(java.lang.String uri) Returns the URI mapping in the catalog for the given URI reference or null if no mapping exists.
void	setCatalogList(java.lang.String[] catalogs) Sets the initial list of catalog entry files.
void	setPreferPublic(boolean preferPublic) Sets the preference for whether system or public matches are preferred.
void	setUseLiteralSystemId(boolean useLiteralSystemId) Sets the preference for whether the literal system identifier should be used when resolving system identifiers when both it and the expanded system identifier are available.

Methods inherited from class java.lang.Object

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

Constructor Detail

XMLCatalogResolver

public XMLCatalogResolver()

Constructs a catalog resolver with a default configuration.

XMLCatalogResolver

public XMLCatalogResolver(java.lang.String[] catalogs)

Constructs a catalog resolver with the given list of entry files.

Parameters:

catalogs - an ordered array list of absolute URIs

XMLCatalogResolver

public XMLCatalogResolver(java.lang.String[] catalogs,
                          boolean preferPublic)

Constructs a catalog resolver with the given list of entry files and the preference for whether system or public matches are preferred.

Parameters:

catalogs - an ordered array list of absolute URIs

preferPublic - the prefer public setting

Method Detail

getCatalogList

public final java.lang.String[] getCatalogList()

Returns the initial list of catalog entry files.

Returns:

the initial list of catalog entry files

setCatalogList

public final void setCatalogList(java.lang.String[] catalogs)

Sets the initial list of catalog entry files. If there were any catalog mappings cached from the previous list they will be replaced by catalog mappings from the new list the next time the catalog is queried.

Parameters:

catalogs - an ordered array list of absolute URIs

clear

public final void clear()

Forces the cache of catalog mappings to be cleared.

getPreferPublic

public final boolean getPreferPublic()

Returns the preference for whether system or public matches are preferred. This is used in the absence of any occurrence of the prefer attribute on the catalog entry of a catalog. If this property has not yet been explicitly set its value is true.

Returns:

the prefer public setting

setPreferPublic

public final void setPreferPublic(boolean preferPublic)

Sets the preference for whether system or public matches are preferred. This is used in the absence of any occurrence of the prefer attribute on the catalog entry of a catalog.

Parameters:

preferPublic - the prefer public setting

getUseLiteralSystemId

public final boolean getUseLiteralSystemId()

Returns the preference for whether the literal system identifier should be used when resolving system identifiers when both it and the expanded system identifier are available. If this property has not yet been explicitly set its value is true.

Returns:

the preference for using literal system identifiers for catalog resolution

See Also:

setUseLiteralSystemId(boolean)

setUseLiteralSystemId

public final void setUseLiteralSystemId(boolean useLiteralSystemId)

Sets the preference for whether the literal system identifier should be used when resolving system identifiers when both it and the expanded system identifier are available.

The literal system identifier is the URI as it was provided before absolutization. It may be embedded within an entity. It may be provided externally or it may be the result of redirection. For example, redirection may have come from the protocol level through HTTP or from an application's entity resolver.

The expanded system identifier is an absolute URI which is the result of resolving the literal system identifier against a base URI.

Parameters:

useLiteralSystemId - the preference for using literal system identifiers for catalog resolution

resolveEntity

public InputSource resolveEntity(java.lang.String publicId,
                                 java.lang.String systemId)
                          throws SAXException,
                                 java.io.IOException

Resolves an external entity. If the entity cannot be resolved, this method should return null. This method returns an input source if an entry was found in the catalog for the given external identifier. It should be overridden if other behaviour is required.

Specified by:

resolveEntity in interface EntityResolver

Parameters:

publicId - the public identifier, or null if none was supplied

systemId - the system identifier

Returns:

An InputSource object describing the new input source, or null to request that the parser open a regular URI connection to the system identifier.

Throws:

SAXException - any SAX exception, possibly wrapping another exception

java.io.IOException - thrown if some i/o error occurs

See Also:

InputSource

resolveEntity

public InputSource resolveEntity(java.lang.String name,
                                 java.lang.String publicId,
                                 java.lang.String baseURI,
                                 java.lang.String systemId)
                          throws SAXException,
                                 java.io.IOException

Resolves an external entity. If the entity cannot be resolved, this method should return null. This method returns an input source if an entry was found in the catalog for the given external identifier. It should be overridden if other behaviour is required.

Specified by:

resolveEntity in interface EntityResolver2

Parameters:

name - the identifier of the external entity

publicId - the public identifier, or null if none was supplied

baseURI - the URI with respect to which relative systemIDs are interpreted.

systemId - the system identifier

Returns:

An InputSource object describing the new input source to be used by the parser. Returning null directs the parser to resolve the system ID against the base URI and open a connection to resulting URI.

Throws:

SAXException - any SAX exception, possibly wrapping another exception

java.io.IOException - thrown if some i/o error occurs

getExternalSubset

public InputSource getExternalSubset(java.lang.String name,
                                     java.lang.String baseURI)
                              throws SAXException,
                                     java.io.IOException

Locates an external subset for documents which do not explicitly provide one. This method always returns null. It should be overrided if other behaviour is required.

Specified by:

getExternalSubset in interface EntityResolver2

Parameters:

name - the identifier of the document root element

baseURI - the document's base URI

Returns:

An InputSource object describing the new external subset to be used by the parser, or null to indicate that no external subset is provided.

Throws:

SAXException - any SAX exception, possibly wrapping another exception

java.io.IOException - thrown if some i/o error occurs

resolveResource

public LSInput resolveResource(java.lang.String type,
                               java.lang.String namespaceURI,
                               java.lang.String publicId,
                               java.lang.String systemId,
                               java.lang.String baseURI)

Resolves a resource using the catalog. This method interprets that the namespace URI corresponds to uri entries in the catalog. Where both a namespace and an external identifier exist, the namespace takes precedence.

Specified by:

resolveResource in interface LSResourceResolver

Parameters:

type - the type of the resource being resolved

namespaceURI - the namespace of the resource being resolved, or null if none was supplied

publicId - the public identifier of the resource being resolved, or null if none was supplied

systemId - the system identifier of the resource being resolved, or null if none was supplied

baseURI - the absolute base URI of the resource being parsed, or null if there is no base URI

Returns:

A LSInput object describing the new input source, or null to request that the parser open a regular URI connection to the resource.

resolveEntity

public XMLInputSource resolveEntity(XMLResourceIdentifier resourceIdentifier)
                             throws XNIException,
                                    java.io.IOException

Resolves an external entity. If the entity cannot be resolved, this method should return null. This method only calls resolveIdentifier and returns an input source if an entry was found in the catalog. It should be overridden if other behaviour is required.

Specified by:

resolveEntity in interface XMLEntityResolver

Parameters:

resourceIdentifier - location of the XML resource to resolve

Throws:

XNIException - thrown on general error

java.io.IOException - thrown if some i/o error occurs

See Also:

XMLResourceIdentifier

resolveIdentifier

public java.lang.String resolveIdentifier(XMLResourceIdentifier resourceIdentifier)
                                   throws java.io.IOException,
                                          XNIException

Resolves an identifier using the catalog. This method interprets that the namespace of the identifier corresponds to uri entries in the catalog. Where both a namespace and an external identifier exist, the namespace takes precedence.

Parameters:

resourceIdentifier - the identifier to resolve

Throws:

XNIException - thrown on general error

java.io.IOException - thrown if some i/o error occurs

resolveSystem

public final java.lang.String resolveSystem(java.lang.String systemId)
                                     throws java.io.IOException

Returns the URI mapping in the catalog for the given external identifier or null if no mapping exists. If the system identifier is an URN in the publicid namespace it is converted into a public identifier by URN "unwrapping" as specified in the XML Catalogs specification.

Parameters:

systemId - the system identifier to locate in the catalog

Returns:

the mapped URI or null if no mapping was found in the catalog

Throws:

java.io.IOException - if an i/o error occurred while reading the catalog

resolvePublic

public final java.lang.String resolvePublic(java.lang.String publicId,
                                            java.lang.String systemId)
                                     throws java.io.IOException

Returns the URI mapping in the catalog for the given external identifier or null if no mapping exists. Public identifiers are normalized before comparison.

Parameters:

publicId - the public identifier to locate in the catalog

systemId - the system identifier to locate in the catalog

Returns:

the mapped URI or null if no mapping was found in the catalog

Throws:

java.io.IOException - if an i/o error occurred while reading the catalog

resolveURI

public final java.lang.String resolveURI(java.lang.String uri)
                                  throws java.io.IOException

Returns the URI mapping in the catalog for the given URI reference or null if no mapping exists. URI comparison is case sensitive. If the URI reference is an URN in the publicid namespace it is converted into a public identifier by URN "unwrapping" as specified in the XML Catalogs specification and then resolution is performed following the semantics of external identifier resolution.

Parameters:

uri - the URI to locate in the catalog

Returns:

the mapped URI or null if no mapping was found in the catalog

Throws:

java.io.IOException - if an i/o error occurred while reading the catalog