xpathquery.java

用Java写的面相对象的数据库管理系统

// You can redistribute this software and/or modify it under the terms of
// the Ozone Library License version 1 published by ozone-db.org.
//
// The original code and portions created by SMB are
// Copyright (C) 1997-2000 by SMB GmbH. All rights reserved.
//
// $Id: XPathQuery.java,v 1.5 2000/10/28 16:55:25 daniela Exp $

package org.ozoneDB.xml.xpath;

import java.io.*;

import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.traversal.NodeFilter;



/**
 * This represents a XPath query, which an {@link XPathProcessor} is able to
 * handle.
 * 
 * 
 * @version $Revision: 1.5 $ $Date: 2000/10/28 16:55:25 $
 * @author <a href="http://www.softwarebuero.de">SMB</a>
 * @see XPathProcessor
 */
public class XPathQuery implements Externalizable {
    
    protected final static long serialVersionUID = 1L;
    
    protected String qstring;
    
    protected NodeFilter filter;
    
    protected Node namespace;
    
    
    /**
     * Initialize this query with the given parameters.
     * @param qString The XPath query string.
     */
    public void init( String _qstring ) {
        init( _qstring, null, null );
    } 
    
    
    /**
     * Initialize this query with the given parameters.
     * @param qString The XPath query string.
     * @param filter The node filter which is to apply while querying.
     */
    public void init( String _qstring, NodeFilter _filter ) {
        init( _qstring, null, _filter );
    } 
    
    
    /**
     * Initialize this query with the given parameters.
     * @param qString The XPath query string.
     * @param rootNode The node from which the query should start.
     * @param nameSpace The node that resolves namespace queries.
     * @param filter The node filter which is to apply while querying.
     */
    public void init( String _qstring, Node _namespace, NodeFilter _filter ) {
        qstring = _qstring;
        filter = _filter;
        namespace = _namespace;
    } 
    
    
    public void writeExternal( ObjectOutput out ) throws IOException {
        out.writeObject( qstring );
        out.writeObject( filter );
        out.writeObject( namespace );
    } 
    
    
    public void readExternal( ObjectInput in ) throws IOException, ClassNotFoundException {
        qstring = (String)in.readObject();
        filter = (NodeFilter)in.readObject();
        namespace = (Node)in.readObject();
    } 
}