org.neo4j.visualization.graphviz.GraphvizRenderer Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of neo4j-graphviz Show documentation

Utility component to generate Graphviz .dot notation from Neo4j graphs.

There is a newer version: 3.2.0-alpha05

/*
 * Copyright (c) 2002-2016 "Neo Technology,"
 * Network Engine for Objects in Lund AB [http://neotechnology.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j 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 3 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, see .
 */
package org.neo4j.visualization.graphviz;

import java.io.IOException;
import java.io.PrintStream;

import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.Relationship;
import org.neo4j.visualization.GraphRenderer;
import org.neo4j.visualization.PropertyRenderer;

class GraphvizRenderer implements GraphRenderer
{
    private final PrintStream stream;
    private final GraphStyle graphStyle;
    private final NodeStyle nodeStyle;
    private final RelationshipStyle edgeStyle;

    GraphvizRenderer( GraphStyle style, PrintStream stream ) throws IOException
    {
        this.stream = stream;
        nodeStyle = style.nodeStyle;
        edgeStyle = style.edgeStyle;
        graphStyle = style;
        graphStyle.emitGraphStart( stream );
    }

    public void done() throws IOException
    {
        graphStyle.emitGraphEnd( stream );
    }

    public PropertyRenderer renderNode( Node node )
        throws IOException
    {
        return new PropertyAdapter( node );
    }

    public PropertyRenderer renderRelationship(
        Relationship relationship ) throws IOException
    {
        return new PropertyAdapter( relationship );
    }

    public GraphvizRenderer renderSubgraph( String name ) throws IOException
    {
        return new GraphvizRenderer( graphStyle.getSubgraphStyle( name ), stream );
    }

    private class PropertyAdapter implements PropertyRenderer
    {
        private final PropertyContainerStyle style;

        PropertyAdapter( Node node ) throws IOException
        {
            nodeStyle.emitNodeStart( stream, node );
            this.style = nodeStyle;
        }

        PropertyAdapter( Relationship relationship ) throws IOException
        {
            edgeStyle.emitRelationshipStart( stream, relationship );
            this.style = edgeStyle;
        }

        public void done() throws IOException
        {
            style.emitEnd( stream );
        }

        public void renderProperty( String propertyKey, Object propertyValue )
            throws IOException
        {
            style.emitProperty( stream, propertyKey, propertyValue );
        }
    }
}