infra.beans.factory.xml.DelegatingEntityResolver Maven / Gradle / Ivy
/*
* Copyright 2017 - 2024 the original author or authors.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see [https://www.gnu.org/licenses/]
*/
package infra.beans.factory.xml;
import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import java.io.IOException;
import infra.lang.Assert;
import infra.lang.Nullable;
/**
* {@link EntityResolver} implementation that delegates to a {@link BeansDtdResolver}
* and a {@link PluggableSchemaResolver} for DTDs and XML schemas, respectively.
*
* @author Rob Harrop
* @author Juergen Hoeller
* @author Rick Evans
* @see BeansDtdResolver
* @see PluggableSchemaResolver
* @since 4.0
*/
public class DelegatingEntityResolver implements EntityResolver {
/** Suffix for DTD files. */
public static final String DTD_SUFFIX = ".dtd";
/** Suffix for schema definition files. */
public static final String XSD_SUFFIX = ".xsd";
private final EntityResolver dtdResolver;
private final EntityResolver schemaResolver;
/**
* Create a new DelegatingEntityResolver that delegates to
* a default {@link BeansDtdResolver} and a default {@link PluggableSchemaResolver}.
* Configures the {@link PluggableSchemaResolver} with the supplied
* {@link ClassLoader}.
*
* @param classLoader the ClassLoader to use for loading
* (can be {@code null}) to use the default ClassLoader)
*/
public DelegatingEntityResolver(@Nullable ClassLoader classLoader) {
this.dtdResolver = new BeansDtdResolver();
this.schemaResolver = new PluggableSchemaResolver(classLoader);
}
/**
* Create a new DelegatingEntityResolver that delegates to
* the given {@link EntityResolver EntityResolvers}.
*
* @param dtdResolver the EntityResolver to resolve DTDs with
* @param schemaResolver the EntityResolver to resolve XML schemas with
*/
public DelegatingEntityResolver(EntityResolver dtdResolver, EntityResolver schemaResolver) {
Assert.notNull(dtdResolver, "'dtdResolver' is required");
Assert.notNull(schemaResolver, "'schemaResolver' is required");
this.dtdResolver = dtdResolver;
this.schemaResolver = schemaResolver;
}
@Override
@Nullable
public InputSource resolveEntity(@Nullable String publicId, @Nullable String systemId)
throws SAXException, IOException {
if (systemId != null) {
if (systemId.endsWith(DTD_SUFFIX)) {
return this.dtdResolver.resolveEntity(publicId, systemId);
}
else if (systemId.endsWith(XSD_SUFFIX)) {
return this.schemaResolver.resolveEntity(publicId, systemId);
}
}
// Fall back to the parser's default behavior.
return null;
}
@Override
public String toString() {
return "EntityResolver delegating " + XSD_SUFFIX + " to " + this.schemaResolver +
" and " + DTD_SUFFIX + " to " + this.dtdResolver;
}
}