/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-04 The eXist Project
* http://exist-db.org
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2
* 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id$
*/
package org.exist.source;
import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import org.exist.dom.BinaryDocument;
import org.exist.dom.DocumentImpl;
import org.exist.security.PermissionDeniedException;
import org.exist.storage.DBBroker;
import org.exist.storage.lock.Lock;
import org.exist.xmldb.XmldbURI;
/**
* Source implementation that reads from a binary resource
* stored in the database.
*
* @author wolf
*/
public class DBSource extends AbstractSource {
private BinaryDocument doc;
private XmldbURI key;
private long lastModified;
private String encoding = "UTF-8";
private boolean checkEncoding;
private DBBroker broker;
public DBSource(DBBroker broker, BinaryDocument doc, boolean checkXQEncoding) {
this.broker = broker;
this.doc = doc;
this.key = doc.getURI();
this.lastModified = doc.getMetadata().getLastModified();
this.checkEncoding = checkXQEncoding;
}
/* (non-Javadoc)
* @see org.exist.source.Source#getKey()
*/
public Object getKey() {
return key;
}
public XmldbURI getDocumentPath() {
return key;
}
public long getLastModified() {
return lastModified;
}
/* (non-Javadoc)
* @see org.exist.source.Source#isValid()
*/
public int isValid(DBBroker broker) {
DocumentImpl doc = null;
try {
doc = broker.getXMLResource(key, Lock.READ_LOCK);
if (doc == null)
return INVALID;
if (doc.getMetadata().getLastModified() > lastModified)
return INVALID;
return VALID;
} catch (PermissionDeniedException e) {
return INVALID;
} finally {
if (doc != null)
doc.getUpdateLock().release(Lock.READ_LOCK);
}
}
/* (non-Javadoc)
* @see org.exist.source.Source#isValid(org.exist.source.Source)
*/
public int isValid(Source other) {
if(!(other instanceof DBSource))
return INVALID;
DBSource source = (DBSource) other;
if(source.getLastModified() > lastModified)
return INVALID;
return VALID;
}
/* (non-Javadoc)
* @see org.exist.source.Source#getReader()
*/
public Reader getReader() throws IOException {
InputStream is = broker.getBinaryResource(doc);
BufferedInputStream bis = new BufferedInputStream(is);
bis.mark(64);
checkEncoding(bis);
bis.reset();
return new InputStreamReader(bis, encoding);
}
public InputStream getInputStream() throws IOException {
return broker.getBinaryResource(doc);
}
/* (non-Javadoc)
* @see org.exist.source.Source#getContent()
*/
public String getContent() throws IOException {
InputStream raw = broker.getBinaryResource(doc);
byte [] data = new byte[(int)broker.getBinaryResourceSize(doc)];
raw.read(data);
raw.close();
ByteArrayInputStream is = new ByteArrayInputStream(data);
checkEncoding(is);
return new String(data, encoding);
}
private void checkEncoding(InputStream is) throws IOException {
if (checkEncoding) {
String checkedEnc = guessXQueryEncoding(is);
if (checkedEnc != null)
encoding = checkedEnc;
}
}
public String toString() {
return doc.getDocumentURI();
}
}