org.apache.xerces.util.EntityResolver2Wrapper Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of xercesImpl Show documentation
Show all versions of xercesImpl Show documentation
Xerces2 is the next generation of high performance, fully compliant XML parsers in the Apache Xerces family.
This new version of Xerces introduces the Xerces Native Interface (XNI), a complete framework for building
parser components and configurations that is extremely modular and easy to program. The Apache Xerces2 parser is
the reference implementation of XNI but other parser components, configurations, and parsers can be written
using the Xerces Native Interface. For complete design and implementation documents, refer to the XNI Manual.
Xerces2 is a fully conforming XML Schema 1.0 processor. A partial experimental implementation of the XML Schema
1.1 Structures and Datatypes Working Drafts (December 2009) and an experimental implementation of the XML Schema
Definition Language (XSD): Component Designators (SCD) Candidate Recommendation (January 2010) are provided for
evaluation. For more information, refer to the XML Schema page. Xerces2 also provides a complete implementation
of the Document Object Model Level 3 Core and Load/Save W3C Recommendations and provides a complete
implementation of the XML Inclusions (XInclude) W3C Recommendation. It also provides support for OASIS XML
Catalogs v1.1. Xerces2 is able to parse documents written according to the XML 1.1 Recommendation, except that
it does not yet provide an option to enable normalization checking as described in section 2.13 of this
specification. It also handles namespaces according to the XML Namespaces 1.1 Recommendation, and will correctly
serialize XML 1.1 documents if the DOM level 3 load/save APIs are in use.
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.xerces.util;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import org.apache.xerces.impl.ExternalSubsetResolver;
import org.apache.xerces.impl.XMLEntityDescription;
import org.apache.xerces.xni.XMLResourceIdentifier;
import org.apache.xerces.xni.XNIException;
import org.apache.xerces.xni.grammars.XMLDTDDescription;
import org.apache.xerces.xni.parser.XMLInputSource;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.ext.EntityResolver2;
/**
* This class wraps a SAX entity resolver (EntityResolver2) in an XNI entity resolver.
*
* @author Michael Glavassevich, IBM
*
* @version $Id: EntityResolver2Wrapper.java 699892 2008-09-28 21:08:27Z mrglavas $
*/
public class EntityResolver2Wrapper
implements ExternalSubsetResolver {
//
// Data
//
/** An instance of SAX2 Extensions 1.1's EntityResolver2. */
protected EntityResolver2 fEntityResolver;
//
// Constructors
//
/** Default constructor. */
public EntityResolver2Wrapper() {}
/**
* Creates a new instance wrapping the given SAX entity resolver.
*
* @param entityResolver the SAX entity resolver to wrap
*/
public EntityResolver2Wrapper(EntityResolver2 entityResolver) {
setEntityResolver(entityResolver);
} // (EntityResolver2)
//
// Public methods
//
/**
* Sets the SAX entity resolver wrapped by this object.
*
* @param entityResolver the SAX entity resolver to wrap
*/
public void setEntityResolver(EntityResolver2 entityResolver) {
fEntityResolver = entityResolver;
} // setEntityResolver(EntityResolver2)
/**
* Returns the SAX entity resolver wrapped by this object.
*
* @return the SAX entity resolver wrapped by this object
*/
public EntityResolver2 getEntityResolver() {
return fEntityResolver;
} // getEntityResolver():EntityResolver2
//
// ExternalSubsetResolver methods
//
/**
* Locates an external subset for documents which do not explicitly
* provide one. If no external subset is provided, this method should
* return null.
*
* @param grammarDescription a description of the DTD
*
* @throws XNIException Thrown on general error.
* @throws IOException Thrown if resolved entity stream cannot be
* opened or some other i/o error occurs.
*/
public XMLInputSource getExternalSubset(XMLDTDDescription grammarDescription)
throws XNIException, IOException {
if (fEntityResolver != null) {
String name = grammarDescription.getRootName();
String baseURI = grammarDescription.getBaseSystemId();
// Resolve using EntityResolver2
try {
InputSource inputSource = fEntityResolver.getExternalSubset(name, baseURI);
return (inputSource != null) ? createXMLInputSource(inputSource, baseURI) : null;
}
// error resolving external subset
catch (SAXException e) {
Exception ex = e.getException();
if (ex == null) {
ex = e;
}
throw new XNIException(ex);
}
}
// unable to resolve external subset
return null;
} // getExternalSubset(XMLDTDDescription):XMLInputSource
//
// XMLEntityResolver methods
//
/**
* Resolves an external parsed entity. If the entity cannot be
* resolved, this method should return null.
*
* @param resourceIdentifier contains the physical co-ordinates of the resource to be resolved
*
* @throws XNIException Thrown on general error.
* @throws IOException Thrown if resolved entity stream cannot be
* opened or some other i/o error occurs.
*/
public XMLInputSource resolveEntity(XMLResourceIdentifier resourceIdentifier)
throws XNIException, IOException {
if (fEntityResolver != null) {
String pubId = resourceIdentifier.getPublicId();
String sysId = resourceIdentifier.getLiteralSystemId();
String baseURI = resourceIdentifier.getBaseSystemId();
String name = null;
if (resourceIdentifier instanceof XMLDTDDescription) {
name = "[dtd]";
}
else if (resourceIdentifier instanceof XMLEntityDescription) {
name = ((XMLEntityDescription) resourceIdentifier).getEntityName();
}
// When both pubId and sysId are null, the user's entity resolver
// can do nothing about it. We'd better not bother calling it.
// This happens when the resourceIdentifier is a GrammarDescription,
// which describes a schema grammar of some namespace, but without
// any schema location hint. -Sg
if (pubId == null && sysId == null) {
return null;
}
// Resolve using EntityResolver2
try {
InputSource inputSource =
fEntityResolver.resolveEntity(name, pubId, baseURI, sysId);
return (inputSource != null) ? createXMLInputSource(inputSource, baseURI) : null;
}
// error resolving entity
catch (SAXException e) {
Exception ex = e.getException();
if (ex == null) {
ex = e;
}
throw new XNIException(ex);
}
}
// unable to resolve entity
return null;
} // resolveEntity(XMLResourceIdentifier):XMLInputSource
/**
* Creates an XMLInputSource from a SAX InputSource.
*/
private XMLInputSource createXMLInputSource(InputSource source, String baseURI) {
String publicId = source.getPublicId();
String systemId = source.getSystemId();
String baseSystemId = baseURI;
InputStream byteStream = source.getByteStream();
Reader charStream = source.getCharacterStream();
String encoding = source.getEncoding();
XMLInputSource xmlInputSource =
new XMLInputSource(publicId, systemId, baseSystemId);
xmlInputSource.setByteStream(byteStream);
xmlInputSource.setCharacterStream(charStream);
xmlInputSource.setEncoding(encoding);
return xmlInputSource;
} // createXMLInputSource(InputSource,String):XMLInputSource
} // class EntityResolver2Wrapper