franta-hg@22: /**
franta-hg@22:  * Alt2XML
franta-hg@22:  * Copyright © 2014 František Kučera (frantovo.cz)
franta-hg@22:  *
franta-hg@22:  * This program is free software: you can redistribute it and/or modify
franta-hg@22:  * it under the terms of the GNU General Public License as published by
franta-hg@111:  * the Free Software Foundation, version 3 of the License.
franta-hg@22:  *
franta-hg@22:  * This program is distributed in the hope that it will be useful,
franta-hg@22:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
franta-hg@22:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
franta-hg@22:  * GNU General Public License for more details.
franta-hg@22:  *
franta-hg@22:  * You should have received a copy of the GNU General Public License
franta-hg@22:  * along with this program. If not, see <http://www.gnu.org/licenses/>.
franta-hg@22:  */
franta-hg@22: package cz.frantovo.alt2xml;
franta-hg@22: 
franta-hg@22: import java.io.IOException;
franta-hg@22: import java.io.InputStream;
franta-hg@22: import java.io.InputStreamReader;
franta-hg@22: import java.io.Reader;
franta-hg@22: import java.io.UnsupportedEncodingException;
franta-hg@22: import java.net.MalformedURLException;
franta-hg@22: import java.net.URL;
franta-hg@22: import java.util.logging.Level;
franta-hg@22: import java.util.logging.Logger;
franta-hg@22: import org.xml.sax.EntityResolver;
franta-hg@22: import org.xml.sax.InputSource;
franta-hg@22: import org.xml.sax.SAXException;
franta-hg@22: 
franta-hg@22: /**
franta-hg@22:  *
franta-hg@22:  * @author Ing. František Kučera (frantovo.cz)
franta-hg@22:  */
franta-hg@22: public class AltInputSource extends InputSource {
franta-hg@22: 
franta-hg@22: 	private final EntityResolver entityResolver;
franta-hg@22: 	private final InputSource originalSource;
franta-hg@22: 
franta-hg@22: 	private static final Logger log = Logger.getLogger(AltInputSource.class.getName());
franta-hg@22: 
franta-hg@22: 	public AltInputSource(EntityResolver entityResolver, InputSource originalSource) {
franta-hg@22: 		this.entityResolver = entityResolver;
franta-hg@22: 		this.originalSource = originalSource;
franta-hg@22: 	}
franta-hg@22: 
franta-hg@22: 	@Override
franta-hg@22: 	public InputStream getByteStream() {
franta-hg@22: 		InputStream originalStream = originalSource.getByteStream();
franta-hg@22: 
franta-hg@22: 		if (originalStream == null) {
franta-hg@22: 
franta-hg@22: 			InputSource source = originalSource;
franta-hg@22: 
franta-hg@22: 			if (entityResolver != null) {
franta-hg@22: 				try {
franta-hg@22: 					InputSource resolvedSource = entityResolver.resolveEntity(originalSource.getSystemId(), originalSource.getSystemId());
franta-hg@22: 					if (resolvedSource != null) {
franta-hg@22: 						source = resolvedSource;
franta-hg@22: 					}
franta-hg@22: 				} catch (IOException | SAXException e) {
franta-hg@22: 					log.log(Level.WARNING, "Error while resolving InputSource – publicId: " + originalSource.getPublicId() + " systemId: " + originalSource.getSystemId(), e);
franta-hg@22: 				}
franta-hg@22: 			}
franta-hg@22: 
franta-hg@22: 			InputStream resolvedStream = source.getByteStream();
franta-hg@22: 
franta-hg@22: 			if (resolvedStream == null) {
franta-hg@22: 
franta-hg@22: 				try {
franta-hg@22: 					URL url = new URL(source.getSystemId());
franta-hg@22: 					return url.openStream();
franta-hg@22: 				} catch (MalformedURLException e) {
franta-hg@22: 					log.log(Level.WARNING, "Invalid SystemId URL syntax: " + originalSource.getSystemId(), e);
franta-hg@22: 					return null;
franta-hg@22: 				} catch (IOException e) {
franta-hg@22: 					log.log(Level.WARNING, "Unable to open stream for systemId: " + originalSource.getSystemId(), e);
franta-hg@22: 					return null;
franta-hg@22: 				}
franta-hg@22: 			} else {
franta-hg@22: 				return resolvedStream;
franta-hg@22: 			}
franta-hg@22: 
franta-hg@22: 		} else {
franta-hg@22: 			return originalStream;
franta-hg@22: 		}
franta-hg@22: 	}
franta-hg@22: 
franta-hg@22: 	@Override
franta-hg@22: 	public Reader getCharacterStream() {
franta-hg@22: 		Reader originalStream = originalSource.getCharacterStream();
franta-hg@22: 
franta-hg@22: 		if (originalStream == null) {
franta-hg@22: 			String encoding = getEncoding();
franta-hg@22: 
franta-hg@22: 			if (encoding == null) {
franta-hg@22: 				return new InputStreamReader(getByteStream());
franta-hg@22: 			} else {
franta-hg@22: 				try {
franta-hg@22: 					return new InputStreamReader(getByteStream(), encoding);
franta-hg@22: 				} catch (UnsupportedEncodingException e) {
franta-hg@22: 					log.log(Level.WARNING, "Invalid encoding: " + encoding, e);
franta-hg@22: 					return null;
franta-hg@22: 				}
franta-hg@22: 			}
franta-hg@22: 		} else {
franta-hg@22: 			return originalStream;
franta-hg@22: 		}
franta-hg@22: 	}
franta-hg@22: 
franta-hg@22: 	@Override
franta-hg@22: 	public String getEncoding() {
franta-hg@22: 		return originalSource.getEncoding();
franta-hg@22: 	}
franta-hg@22: 
franta-hg@22: 	@Override
franta-hg@22: 	public String getPublicId() {
franta-hg@22: 		return originalSource.getPublicId();
franta-hg@22: 	}
franta-hg@22: 
franta-hg@22: 	@Override
franta-hg@22: 	public String getSystemId() {
franta-hg@22: 		return originalSource.getSystemId();
franta-hg@22: 	}
franta-hg@36: 
franta-hg@36: 	@Override
franta-hg@36: 	public String toString() {
franta-hg@36: 		return "AltInputSource: systemId=" + getSystemId() + " publicId=" + getPublicId();
franta-hg@36: 	}
franta-hg@22: }