/*
* Copyright 2017 Graz University of Technology EAAF-Core Components has been developed in a
* cooperation between EGIZ, A-SIT Plus, A-SIT, and Graz University of Technology.
*
* Licensed under the EUPL, Version 1.2 or - as soon they will be approved by the European
* Commission - subsequent versions of the EUPL (the "Licence"); You may not use this work except in
* compliance with the Licence. You may obtain a copy of the Licence at:
* https://joinup.ec.europa.eu/news/understanding-eupl-v12
*
* Unless required by applicable law or agreed to in writing, software distributed under the Licence
* is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
* or implied. See the Licence for the specific language governing permissions and limitations under
* the Licence.
*
* This product combines work with different licenses. See the "NOTICE" text file for details on the
* various modules and licenses. The "NOTICE" text file is part of the distribution. Any derivative
* works that you distribute must include a readable copy of the "NOTICE" text file.
*/
package at.gv.egiz.eaaf.core.impl.utils;
import java.io.InputStream;
import org.apache.xerces.util.URI;
import org.apache.xerces.util.URI.MalformedURIException;
import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;
import at.gv.egiz.eaaf.core.api.data.XmlNamespaceConstants;
/**
* An EntityResolver
that looks up entities stored as local
* resources.
*
*
* The following DTDs are mapped to local resources: *
Constants.SCHEMA_ROOT
.
*
*/
public class EaafDomEntityResolver implements EntityResolver {
/**
* Resolve an entity.
*
* The systemId
parameter is used to perform the lookup of the
* entity as a resource, either by interpreting the systemId
as an
* absolute resource path, or by appending the last path component of
* systemId
to Constants.SCHEMA_ROOT
.
*
InputSource
from which the entity can be read, or
* null
, if the entity could not be found.
* @see org.xml.sax.EntityResolver#resolveEntity(java.lang.String,
* java.lang.String)
*/
@Override
public InputSource resolveEntity(final String publicId, String systemId) {
InputStream stream;
int slashPos;
if (publicId != null) {
// check if we can resolve some standard dtd's
if (publicId.equalsIgnoreCase("-//W3C//DTD XMLSchema 200102//EN")) {
return new InputSource(
getClass().getResourceAsStream(XmlNamespaceConstants.SCHEMA_ROOT + "XMLSchema.dtd"));
} else if (publicId.equalsIgnoreCase("datatypes")) {
return new InputSource(
getClass().getResourceAsStream(XmlNamespaceConstants.SCHEMA_ROOT + "datatypes.dtd"));
}
} else if (systemId != null) {
// get the URI path
try {
final URI uri = new URI(systemId);
systemId = uri.getPath();
if (!"file".equals(uri.getScheme()) || "".equals(systemId.trim())) {
return null;
}
} catch (final MalformedURIException e) {
return null;
}
// try to get the resource from the full path
stream = getClass().getResourceAsStream(systemId);
if (stream != null) {
final InputSource source = new InputSource(stream);
source.setSystemId(systemId);
return source;
}
// try to get the resource from the last path component
slashPos = systemId.lastIndexOf('/');
if (slashPos >= 0 && systemId.length() > slashPos) {
systemId = systemId.substring(slashPos + 1, systemId.length());
stream = getClass().getResourceAsStream(XmlNamespaceConstants.SCHEMA_ROOT + systemId);
if (stream != null) {
final InputSource source = new InputSource(stream);
source.setSystemId(systemId);
return source;
}
}
}
return null; // nothing found - let the parser handle the entity
}
}