[ http://issues.apache.org/jira/browse/XERCESJ-1158?page=comments#action_12375667 ]
Michael Glavassevich commented on XERCESJ-1158: ----------------------------------------------- A target namespace is not a schema location, nor is it a public identifier. SAX's entity resolver was only designed for resolving external entities (the external DTD subset, external parameter entities, external general entities). Andrew Jacobs acknowledges that in the document you've attached. Several people have argued that Xerces' treatment of schema locations as system identifiers is wrong. I agree with them in principle but there really was no other option for SAX and its now legacy behaviour anyways. Passing a schema's target namespace in place of the public identifier to an EntityResolver would be even more egregious. It would be difficult to justify such a change, particularly since there are better options in JAXP 1.3. I think Andrew must have written this document before JAXP 1.3 existed (or isn't aware of it). JAXP 1.3 introduced a validation API (javax.xml.validation) [1][2] which decouples validation from parsing. The schema processing facilities in the .NET framework described by Andrew sound very similar to this API. Both the SchemaFactory [3] and the Validator [4] use DOM Level 3's LSResourceResolver [5] for resolving schemas. LSResourceResolver was designed for schema resolution. One of the parameters passed to LSResolverResolver.resolveResource() is a namespace URI which will be the target namespace of the XML schema when the type parameter is equal to "http://www.w3.org/2001/XMLSchema";. This resolver will be called even when no schema location hint is provided. [1] http://www-128.ibm.com/developerworks/xml/library/x-jaxp13a.html#N101AE [2] http://xerces.apache.org/xerces2-j/javadocs/api/javax/xml/validation/package-summary.html [3] http://xerces.apache.org/xerces2-j/javadocs/api/javax/xml/validation/SchemaFactory.html [4] http://xerces.apache.org/xerces2-j/javadocs/api/javax/xml/validation/Validator.html [5] http://xerces.apache.org/xerces2-j/javadocs/api/org/w3c/dom/ls/LSResourceResolver.html > Entity resolver is not applied to namespace URI when used as possible Schema > location > ------------------------------------------------------------------------------------- > > Key: XERCESJ-1158 > URL: http://issues.apache.org/jira/browse/XERCESJ-1158 > Project: Xerces2-J > Type: Bug > Versions: 2.8.0 > Reporter: Anthony B. Coates > Attachments: Correctly Resolving Schema Namespace URLs.doc > > When Xerces-J uses the namespace URI as a possible Schema location, it > bypasses the entity resolver. This means that there is no way to resolve the > Schema to a local copy when there is no explicit "schemaLocation". This is a > major problem in enterprise scenarios where the schemaLocation in incoming > XML messages may not be trustworthy, and only the namespace URI can be used > to resolve the correct Schema for processing. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
