Package gov.nasa.pds.tools.label

Class XMLCatalogResolver

  • All Implemented Interfaces:
    org.apache.xerces.xni.parser.XMLEntityResolver, LSResourceResolver, EntityResolver, EntityResolver2
    public class XMLCatalogResolver
extends CachedLSResourceResolver
implements org.apache.xerces.xni.parser.XMLEntityResolver, EntityResolver2

    Adaption of Xerces XMLCatalogResolver to bootstrap in catalog 1.1 support. In addition the resolveIdentifier method differs in that it does not resolve schema includes based on URIs as is the default behavior with the Xerces version.

    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.

    • Constructor Detail

      • XMLCatalogResolver

        public XMLCatalogResolver()

        Constructs a catalog resolver with a default configuration.

      • XMLCatalogResolver

        public XMLCatalogResolver​(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​(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 String[] getCatalogList()

        Returns the initial list of catalog entry files.

        Returns:
        the initial list of catalog entry files

      • setCatalogList

        public final void setCatalogList​(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​(String publicId,
                                 String systemId)
                          throws SAXException,
                                 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
        Throws:
        SAXException - any SAX exception, possibly wrapping another exception
        IOException - thrown if some i/o error occurs

      • resolveEntity

        public InputSource resolveEntity​(String name,
                                 String publicId,
                                 String baseURI,
                                 String systemId)
                          throws SAXException,
                                 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
        Throws:
        SAXException - any SAX exception, possibly wrapping another exception
        IOException - thrown if some i/o error occurs

      • getExternalSubset

        public InputSource getExternalSubset​(String name,
                                     String baseURI)
                              throws SAXException,
                                     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
        Throws:
        SAXException - any SAX exception, possibly wrapping another exception
        IOException - thrown if some i/o error occurs

      • resolveResource

        public LSInput resolveResource​(String type,
                               String namespaceURI,
                               String publicId,
                               String systemId,
                               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
        Overrides:
        resolveResource in class CachedLSResourceResolver
        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

      • getLSInputFromResolvableResource

        public LSInput getLSInputFromResolvableResource​(String schemaUrl)

      • resolveEntity

        public org.apache.xerces.xni.parser.XMLInputSource resolveEntity​(org.apache.xerces.xni.XMLResourceIdentifier resourceIdentifier)
                                                          throws org.apache.xerces.xni.XNIException,
                                                                 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 org.apache.xerces.xni.parser.XMLEntityResolver
        Parameters:
        resourceIdentifier - location of the XML resource to resolve
        Throws:
        org.apache.xerces.xni.XNIException - thrown on general error
        IOException - thrown if some i/o error occurs

      • resolveSystem

        public final String resolveSystem​(String systemId)
                           throws 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:
        IOException - if an i/o error occurred while reading the catalog

      • resolvePublic

        public final String resolvePublic​(String publicId,
                                  String systemId)
                           throws 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:
        IOException - if an i/o error occurred while reading the catalog

      • resolveURI

        public final String resolveURI​(String uri)
                        throws 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:
        IOException - if an i/o error occurred while reading the catalog

      • resolveIdentifier

        public String resolveIdentifier​(org.apache.xerces.xni.XMLResourceIdentifier resourceIdentifier)
                         throws org.apache.xerces.xni.XNIException,
                                IOException

        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:
        org.apache.xerces.xni.XNIException - thrown on general error
        IOException - thrown if some i/o error occurs