querydecoder.java

一个工作流设计及定义的系统,可以直接与数据库结合进行系统工作流程的定义及应用.

/*
 * Copyright (c) 2005, John Mettraux, OpenWFE.org
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 * 
 * . Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.  
 * 
 * . Redistributions in binary form must reproduce the above copyright notice, 
 *   this list of conditions and the following disclaimer in the documentation 
 *   and/or other materials provided with the distribution.
 * 
 * . Neither the name of the "OpenWFE" nor the names of its contributors may be
 *   used to endorse or promote products derived from this software without
 *   specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * $Id: QueryDecoder.java,v 1.9 2005/05/17 16:41:07 jmettraux Exp $
 */

//
// QueryDecoder.java
//
// [e-mail]
//
// generated with 
// jtmpl 1.1.00 16.08.2003 John Mettraux ([e-mail])
//

package openwfe.org.xdbc.query;

import openwfe.org.xml.XmlUtils;
import openwfe.org.xdbc.XdbcException;


/**
 * Decoding a query from xml
 *
 * <p><font size=2>CVS Info :
 * <br>$Author: jmettraux $
 * <br>$Id: QueryDecoder.java,v 1.9 2005/05/17 16:41:07 jmettraux Exp $ </font>
 *
 * @author [e-mail]
 */
public abstract class QueryDecoder
{

    private final static org.apache.log4j.Logger log = org.apache.log4j.Logger
        .getLogger(QueryDecoder.class.getName());

    //
    // CONSTANTS & co

    protected static java.util.HashMap classMap = new java.util.HashMap();
    static
    {
        classMap.put
            ("or", OrQueryItem.class);
        classMap.put
            ("and", AndQueryItem.class);
        classMap.put
            ("not", NotQueryItem.class);
        classMap.put
            ("elt-query", ElementQueryItem.class);
        classMap.put
            ("att-query", AttributeQueryItem.class);
        classMap.put
            ("owfe-query", OwfeQueryItem.class);
        classMap.put
            ("all", AllQueryItem.class);
    }

    //
    // FIELDS

    //
    // CONSTRUCTORS

    //
    // METHODS

    public static QueryItem decode (String xmlString)
        throws XdbcException
    {
        org.jdom.Document doc = null;
        try
        {
            doc = XmlUtils.extractXmlDocument(xmlString, false);
        }
        catch (Exception e)
        {
            throw new XdbcException
                ("Failed to decode XML string", e);
        }

        return decode(doc.getRootElement());
    }

    public static QueryItem decode (org.jdom.Element elt)
        throws XdbcException
    {
        Class queryItemClass = (Class)classMap.get(elt.getName());

        //if (queryItemClass == null) return null;

        return decode(queryItemClass, elt);
    }

    //
    // PRIVATE METHODS

    private static QueryItem decode (Class queryItemClass, org.jdom.Element elt)
        throws XdbcException
    {
        try
        {
            java.lang.reflect.Method m = queryItemClass
                .getMethod("decode", new Class[] { org.jdom.Element.class });

            return (QueryItem)m.invoke(null, new Object[] { elt });
        }
        catch (Exception e)
        {
            throw new XdbcException
                ("Failed to decode element named '"+elt.getName()+"'", e);
        }
    }

}