/* ==========================================
* JGraphT : a free Java graph-theory library
* ==========================================
*
* Project Info: http://jgrapht.sourceforge.net/
* Project Creator: Barak Naveh (http://sourceforge.net/users/barak_naveh)
*
* (C) Copyright 2003-2008, by Barak Naveh and Contributors.
*
* This program and the accompanying materials are dual-licensed under
* either
*
* (a) the terms of the GNU Lesser General Public License version 2.1
* as published by the Free Software Foundation, or (at your option) any
* later version.
*
* or (per the licensee's choosing)
*
* (b) the terms of the Eclipse Public License v1.0 as published by
* the Eclipse Foundation.
*/
/* ------------------
* GmlExporter.java
* ------------------
* (C) Copyright 2006, by Dimitrios Michail.
*
* Original Author: Dimitrios Michail <dmichail@yahoo.com>
*
* $Id$
*
* Changes
* -------
* 15-Dec-2006 : Initial Version (DM);
*
*/
package org.jgrapht.ext;
import java.io.*;
import org.jgrapht.*;
/**
* Exports a graph into a GML file (Graph Modelling Language).
*
* <p>For a description of the format see <a
* href="http://www.infosun.fmi.uni-passau.de/Graphlet/GML/">
* http://www.infosun.fmi.uni-passau.de/Graphlet/GML/</a>.</p>
*
* <p>The objects associated with vertices and edges are exported as labels
* using their toString() implementation. See the {@link
* #setPrintLabels(Integer)} method. The default behavior is to export no label
* information.</p>
*
* @author Dimitrios Michail
*/
public class GmlExporter<V, E>
{
private static final String creator = "JGraphT GML Exporter";
private static final String version = "1";
private static final String delim = " ";
private static final String tab1 = "\t";
private static final String tab2 = "\t\t";
// TODO jvs 27-Jan-2008: convert these to enum
/**
* Option to export no vertex or edge labels.
*/
public static final Integer PRINT_NO_LABELS = 1;
/**
* Option to export only the edge labels.
*/
public static final Integer PRINT_EDGE_LABELS = 2;
/**
* Option to export both edge and vertex labels.
*/
public static final Integer PRINT_EDGE_VERTEX_LABELS = 3;
/**
* Option to export only the vertex labels.
*/
public static final Integer PRINT_VERTEX_LABELS = 4;
private Integer printLabels = PRINT_NO_LABELS;
private VertexNameProvider<V> vertexIDProvider;
private VertexNameProvider<V> vertexLabelProvider;
private EdgeNameProvider<E> edgeIDProvider;
private EdgeNameProvider<E> edgeLabelProvider;
/**
* Creates a new GmlExporter object with integer name providers for the
* vertex and edge IDs and null providers for the vertex and edge labels.
*/
public GmlExporter()
{
this(
new IntegerNameProvider<V>(),
null,
new IntegerEdgeNameProvider<E>(),
null);
}
/**
* Constructs a new GmlExporter object with the given ID and label
* providers.
*
* @param vertexIDProvider for generating vertex IDs. Must not be null.
* @param vertexLabelProvider for generating vertex labels. If null, vertex
* labels will be generated using the toString() method of the vertex
* object.
* @param edgeIDProvider for generating vertex IDs. Must not be null.
* @param edgeLabelProvider for generating edge labels. If null, edge labels
* will be generated using the toString() method of the edge object.
*/
public GmlExporter(
VertexNameProvider<V> vertexIDProvider,
VertexNameProvider<V> vertexLabelProvider,
EdgeNameProvider<E> edgeIDProvider,
EdgeNameProvider<E> edgeLabelProvider)
{
this.vertexIDProvider = vertexIDProvider;
this.vertexLabelProvider = vertexLabelProvider;
this.edgeIDProvider = edgeIDProvider;
this.edgeLabelProvider = edgeLabelProvider;
}
private String quoted(final String s)
{
return "\"" + s + "\"";
}
private void exportHeader(PrintWriter out)
{
out.println("Creator" + delim + quoted(creator));
out.println("Version" + delim + version);
}
private void exportVertices(
PrintWriter out,
Graph<V, E> g)
{
for (V from : g.vertexSet()) {
out.println(tab1 + "node");
out.println(tab1 + "[");
out.println(
tab2 + "id" + delim + vertexIDProvider.getVertexName(from));
if ((printLabels == PRINT_VERTEX_LABELS)
|| (printLabels == PRINT_EDGE_VERTEX_LABELS))
{
String label =
(vertexLabelProvider == null) ? from.toString()
: vertexLabelProvider.getVertexName(from);
out.println(tab2 + "label" + delim + quoted(label));
}
out.println(tab1 + "]");
}
}
private void exportEdges(
PrintWriter out,
Graph<V, E> g)
{
for (E edge : g.edgeSet()) {
out.println(tab1 + "edge");
out.println(tab1 + "[");
String id = edgeIDProvider.getEdgeName(edge);
out.println(tab2 + "id" + delim + id);
String s = vertexIDProvider.getVertexName(g.getEdgeSource(edge));
out.println(tab2 + "source" + delim + s);
String t = vertexIDProvider.getVertexName(g.getEdgeTarget(edge));
out.println(tab2 + "target" + delim + t);
if ((printLabels == PRINT_EDGE_LABELS)
|| (printLabels == PRINT_EDGE_VERTEX_LABELS))
{
String label =
(edgeLabelProvider == null) ? edge.toString()
: edgeLabelProvider.getEdgeName(edge);
out.println(tab2 + "label" + delim + quoted(label));
}
out.println(tab1 + "]");
}
}
private void export(Writer output, Graph<V, E> g, boolean directed)
{
PrintWriter out = new PrintWriter(output);
for (V from : g.vertexSet()) {
// assign ids in vertex set iteration order
vertexIDProvider.getVertexName(from);
}
exportHeader(out);
out.println("graph");
out.println("[");
out.println(tab1 + "label" + delim + quoted(""));
if (directed) {
out.println(tab1 + "directed" + delim + "1");
} else {
out.println(tab1 + "directed" + delim + "0");
}
exportVertices(out, g);
exportEdges(out, g);
out.println("]");
out.flush();
}
/**
* Exports an undirected graph into a plain text file in GML format.
*
* @param output the writer to which the graph to be exported
* @param g the undirected graph to be exported
*/
public void export(Writer output, UndirectedGraph<V, E> g)
{
export(output, g, false);
}
/**
* Exports a directed graph into a plain text file in GML format.
*
* @param output the writer to which the graph to be exported
* @param g the directed graph to be exported
*/
public void export(Writer output, DirectedGraph<V, E> g)
{
export(output, g, true);
}
/**
* Set whether to export the vertex and edge labels. The default behavior is
* to export no vertex or edge labels.
*
* @param i What labels to export. Valid options are {@link
* #PRINT_NO_LABELS}, {@link #PRINT_EDGE_LABELS}, {@link
* #PRINT_EDGE_VERTEX_LABELS}, and {@link #PRINT_VERTEX_LABELS}.
*
* @throws IllegalArgumentException if a non-supported value is used
*
* @see #PRINT_NO_LABELS
* @see #PRINT_EDGE_LABELS
* @see #PRINT_EDGE_VERTEX_LABELS
* @see #PRINT_VERTEX_LABELS
*/
public void setPrintLabels(final Integer i)
{
if ((i != PRINT_NO_LABELS)
&& (i != PRINT_EDGE_LABELS)
&& (i != PRINT_EDGE_VERTEX_LABELS)
&& (i != PRINT_VERTEX_LABELS))
{
throw new IllegalArgumentException(
"Non-supported parameter value: " + Integer.toString(i));
}
printLabels = i;
}
/**
* Get whether to export the vertex and edge labels.
*
* @return One of the {@link #PRINT_NO_LABELS}, {@link #PRINT_EDGE_LABELS},
* {@link #PRINT_EDGE_VERTEX_LABELS}, or {@link #PRINT_VERTEX_LABELS}.
*/
public Integer getPrintLabels()
{
return printLabels;
}
}
// End GmlExporter.java