Resolver.java

/*
 * 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.cocoon.components.resolver;

import org.apache.avalon.framework.component.Component;
import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import java.io.IOException;

/**
 * A component that uses catalogs for resolving entities.
 * @deprecated Use the Avalon Excalibur EntityResolver instead
 *
 * @author <a href="mailto:dims@yahoo.com">Davanum Srinivas</a>
 * @author <a href="mailto:crossley@apache.org">David Crossley</a>
 * @version CVS $Id$
 */
public interface Resolver extends Component, EntityResolver {

    String ROLE = "org.apache.cocoon.components.resolver.Resolver";

    /**
     * Allow the application to resolve external entities.
     *
     * <p>The Parser will call this method before opening any external
     * entity except the top-level document entity (including the
     * external DTD subset, external entities referenced within the
     * DTD, and external entities referenced within the document
     * element): the application may request that the parser resolve
     * the entity itself, that it use an alternative URI, or that it
     * use an entirely different input source.</p>
     *
     * <p>Application writers can use this method to redirect external
     * system identifiers to secure and/or local URIs, to look up
     * public identifiers in a catalogue, or to read an entity from a
     * database or other input source (including, for example, a dialog
     * box).</p>
     *
     * <p>If the system identifier is a URL, the SAX parser must
     * resolve it fully before reporting it to the application.</p>
     *
     * @param publicId The public identifier of the external entity
     *        being referenced, or null if none was supplied.
     * @param systemId The system identifier of the external entity
     *        being referenced.
     * @return An InputSource object describing the new input source,
     *         or null to request that the parser open a regular
     *         URI connection to the system identifier.
     * @exception org.xml.sax.SAXException Any SAX exception, possibly
     *            wrapping another exception.
     * @exception java.io.IOException A Java-specific IO exception,
     *            possibly the result of creating a new InputStream
     *            or Reader for the InputSource.
     * @see org.xml.sax.InputSource
     */
    InputSource resolveEntity(String publicId, String systemId)
        throws SAXException, IOException;
}