PDLData.java

/*
    Nord Modular Midi Protocol 3.03 Library
    Copyright (C) 2003-2006 Marcus Andersson

    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.sf.nmedit.jnmprotocol2;

import java.io.BufferedReader;
import java.io.File;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.MalformedURLException;
import java.net.URL;

import net.sf.nmedit.jnmprotocol2.PDLData;
import net.sf.nmedit.jpdl2.dom.PDLDocument;
import net.sf.nmedit.jpdl2.format.PDL2Parser;

public final class PDLData
{

    public static final String DEFAULT_MIDI_PDL_LOCATION = "/midi.pdl2";
    public static final String DEFAULT_PATCH_PDL_LOCATION = "/patch.pdl2";
    
    private static String midiPDLLocation = DEFAULT_MIDI_PDL_LOCATION;
    private static String patchPDLLocation = DEFAULT_PATCH_PDL_LOCATION;

    private static ClassLoader loader;

    private static PDLDocument midiDoc;
    private static PDLDocument patchDoc;
    
    private static PDLDocument parseDoc(String file)
    {

        ClassLoader loader = getPDLClassLoader();

        URL resource = null; 
            
        File abs = new File(file);
        if (abs.exists())
        {
            try
            {
                resource = abs.toURI().toURL();
            }
            catch (MalformedURLException e)
            {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        
        if (resource == null)
            resource = loader.getResource(file);
        
        if (resource == null)
            throw new RuntimeException("could not initialize protocol: "+file);
        
        PDLDocument doc;
        Reader reader;
        try
        {
            reader = new BufferedReader(new InputStreamReader(resource.openStream()));

            PDL2Parser parser = new PDL2Parser(reader);

            parser.parse();

            reader.close();
            doc = parser.getDocument();
        }
        catch (Exception e1)
        {
            throw new RuntimeException("could not parse: "+file, e1);
        }

        return doc;
    }
    
    public static PDLDocument getMidiDoc()
    {
        if (midiDoc == null)
        {
            midiDoc = parseDoc(midiPDLLocation);
        }
        return midiDoc;
    }

    public static PDLDocument getPatchDoc()
    {
        if (patchDoc == null)
        {
            patchDoc = parseDoc(patchPDLLocation);
        }
        return patchDoc;
    }

    /**
     * Sets the locations of the pdl files and the class loader which
     * is used to locate the files.
     * 
     * If the specified class loader is null, then the class loader of
     * PDLData will be used.
     * 
     * @param loader the class loader which locates  the pdl files
     * @param midiPDLLocation the location of the midi.pdl file
     * @param patchPDLLocation the location of the patch.pdl file
     */
    public static void setSource(ClassLoader loader, String midiPDLLocation, 
            String patchPDLLocation)
    {
        PDLData.loader = loader;
        PDLData.midiPDLLocation = midiPDLLocation;
        PDLData.patchPDLLocation = patchPDLLocation;
        
        reset();
    }
    
    /**
     * Deletes references to the used protocols.
     * The protocol variables will be automaticall reinitialized.  
     */
    public static void reset()
    {
        patchDoc = null;
        midiDoc = null;
    }
    
    /**
     * The class loader used to locate the pdl files.
     */
    public static ClassLoader getPDLClassLoader()
    {
        if (loader == null)
            loader = PDLData.class.getClassLoader();
        
        return loader;
    }
    
    /**
     * Returns the location of the midi pdl file.
     */
    public static String getMidiPDLLocation()
    {
        return midiPDLLocation;
    }

    /**
     * Returns the location of the patch pdl file.
     */
    public static String getPatchPDLLocation()
    {
        return patchPDLLocation;
    }

}