GraphPersistenceProvider.java

/*
 Copyright 2008-2010 Gephi
 Authors : Mathieu Bastian <mathieu.bastian@gephi.org>
 Website : http://www.gephi.org

 This file is part of Gephi.

 DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

 Copyright 2011 Gephi Consortium. All rights reserved.

 The contents of this file are subject to the terms of either the GNU
 General Public License Version 3 only ("GPL") or the Common
 Development and Distribution License("CDDL") (collectively, the
 "License"). You may not use this file except in compliance with the
 License. You can obtain a copy of the License at
 http://gephi.org/about/legal/license-notice/
 or /cddl-1.0.txt and /gpl-3.0.txt. See the License for the
 specific language governing permissions and limitations under the
 License.  When distributing the software, include this License Header
 Notice in each file and include the License files at
 /cddl-1.0.txt and /gpl-3.0.txt. If applicable, add the following below the
 License Header, with the fields enclosed by brackets [] replaced by
 your own identifying information:
 "Portions Copyrighted [year] [name of copyright owner]"

 If you wish your version of this file to be governed by only the CDDL
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 "[Contributor] elects to include this software in this distribution
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 However, if you add GPL Version 3 code and therefore, elected the GPL
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 Contributor(s):

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 */
package org.gephi.graph;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.gephi.graph.api.GraphModel;
import org.gephi.project.api.Workspace;
import org.gephi.project.spi.WorkspaceBytesPersistenceProvider;
import org.gephi.project.spi.WorkspacePersistenceProvider;
import org.openide.util.lookup.ServiceProvider;

@ServiceProvider(service = WorkspacePersistenceProvider.class, position = 100)
public class GraphPersistenceProvider implements WorkspaceBytesPersistenceProvider {

    @Override
    public void writeBytes(DataOutputStream stream, Workspace workspace) {
        GraphModel model = workspace.getLookup().lookup(GraphModel.class);
        if (model != null) {
            try {
                GraphModel.Serialization.write(stream, model);
            } catch (IOException ex) {
                Logger.getLogger("").log(Level.SEVERE, "", ex.getCause());
            }
        }
    }

    private static final int GRAPHSTORE_SERIALIZATION_GRAPHMODEL_CONFIG_ID = 205;
    
    @Override
    public void readBytes(DataInputStream stream, Workspace workspace) {
        GraphModel model = workspace.getLookup().lookup(GraphModel.class);
        if (model != null) {
            throw new IllegalStateException("The graphModel wasn't null");
        }
        try {
            //Detect if the serialized graphstore declares its own version:
            stream.mark(1);
            int firstFieldType = stream.readUnsignedByte();
            stream.reset();
            
            if (firstFieldType == GRAPHSTORE_SERIALIZATION_GRAPHMODEL_CONFIG_ID) {
                //Old graphstore, from Gephi 0.9.0
                model = GraphModel.Serialization.readWithoutVersionHeader(stream, 0.0f /* no version, first was 0.4*/);//Previous to version header existing at all
            } else {
                model = GraphModel.Serialization.read(stream);
            }

            workspace.add(model);
        } catch (IOException ex) {
            throw new RuntimeException(ex);
        }
    }

    @Override
    public String getIdentifier() {
        return "graphstore";
    }
}