// XmlBlacklistImporter.java
// -------------------------------------
// part of YACY
//
// (C) 2009 by Marc Nause
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// 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 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package net.yacy.data.list;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import org.apache.xerces.parsers.SAXParser;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
/**
* This class provides methods to import blacklists from an XML file (see
* http://www.yacy-websuche.de/wiki/index.php/Dev:APIblacklists
* for examples) and to return this data as a {@link ListAccumulator} object.
*/
public class XMLBlacklistImporter extends DefaultHandler {
private ListAccumulator ba = null;
private String currentListName = null;
private StringBuilder lastText = null;
/**
* Takes the input data and turns it into a {@link ListAccumulator} which can
* be used for further processing.
* @param input the XML data
* @return the data from the XML
* @throws java.io.IOException if input can't be read
* @throws org.xml.sax.SAXException if XML can't be parsed
*/
public synchronized ListAccumulator parse(InputSource input) throws IOException, SAXException {
XMLReader reader = new SAXParser();
reader.setContentHandler(this);
reader.parse(input);
return ba;
}
/**
* Takes the input data and turns it into a {@link ListAccumulator} which can
* be used for further processing.
* @param input the XML data
* @return the data from the XML
* @throws java.io.IOException if input can't be read
* @throws org.xml.sax.SAXException if XML can't be parsed
*/
public synchronized ListAccumulator parse(Reader input) throws IOException, SAXException {
return this.parse(new InputSource(input));
}
/**
* Takes the input data and turns it into a {@link ListAccumulator} which can
* be used for further processing.
* @param input the XML data
* @return the data from the XML
* @throws java.io.IOException if input can't be read
* @throws org.xml.sax.SAXException if XML can't be parsed
*/
public synchronized ListAccumulator parse(String input) throws IOException, SAXException {
return this.parse(new InputSource(input));
}
/**
* Takes the input data and turns it into a {@link ListAccumulator} which can
* be used for further processing.
* @param input The XML data.
* @return The data from the XML.
* @throws java.io.IOException if input can't be read
* @throws org.xml.sax.SAXException if XML can't be parsed
*/
public synchronized ListAccumulator parse(InputStream input) throws IOException, SAXException {
return this.parse(new InputSource(input));
}
/**
* At the start of the document a new {@link ListAccumulator} is created.
*/
@Override
public void startDocument() {
ba = new ListAccumulator();
}
/**
* If the <list> tag is encountered a new list will be addedto the
* {@link ListAccumulator} and the properties of the list will be set
* if provided in the XML.
* @param uri The Namespace URI, or the empty string if the
* element has no Namespace URI or if Namespace
* processing is not being performed.
* @param localName The local name (without prefix), or the
* empty string if Namespace processing is not being
* performed.
* @param qName The qualified name (with prefix), or the
* empty string if qualified names are not available.
* @param attributes The attributes attached to the element. If
* there are no attributes, it shall be an empty
* Attributes object.
*/
@Override
public void startElement(final String uri, final String localName, final String qName, final Attributes attributes) {
if (qName.equalsIgnoreCase("list")) {
currentListName = attributes.getValue("name");
ba.addList(currentListName);
int attributesLength = 0;
if ((attributesLength = attributes.getLength()) > 1) {
for (int i = 0; i < attributesLength; i++) {
if (!attributes.getQName(i).equals("name")) {
ba.addPropertyToCurrent(attributes.getQName(i), attributes.getValue(i));
}
}
}
}
if (qName.equalsIgnoreCase("item")) {
lastText = new StringBuilder();
}
}
/**
* Adds a new item to the current list in the {@link ListAccumulator}.
* @param uri The Namespace URI, or the empty string if the
* element has no Namespace URI or if Namespace
* processing is not being performed.
* @param localName The local name (without prefix), or the
* empty string if Namespace processing is not being
* performed.
* @param qName The qualified name (with prefix), or the
* empty string if qualified names are not available.
* @throws org.xml.sax.SAXException
*/
@Override
public void endElement(final String uri, final String localName, final String qName) throws SAXException {
if (qName.equalsIgnoreCase("item")) {
ba.addEntryToCurrent(lastText.toString());
}
}
/**
* Writes characters to a String which might be used by endElement() later.
* @param ch The characters.
* @param start The start position in the character array.
* @param length The number of characters to use from the character array.
* @throws org.xml.sax.SAXException
*/
@Override
public void characters(char[] ch, int start, int length) throws SAXException {
if (lastText == null) lastText = new StringBuilder();
lastText.append(ch, start, length);
}
}