private void writeVertex(Writer writer, Vertex v, int id) throws IOException {
writer.write(TAB);
writer.write(GMLTokens.NODE);
writer.write(OPEN_LIST);
writeKey(writer, GMLTokens.ID);
writeNumberProperty(writer, id);
writeVertexProperties(writer, v);
writer.write(TAB);
writer.write(CLOSE_LIST);
}
private void writeGraph(Writer writer, List<Vertex> verticies, List<Edge> edges)
throws IOException {
Map<Vertex, Integer> ids = new HashMap<Vertex, Integer>();
writer.write(GMLTokens.GRAPH);
writer.write(OPEN_LIST);
writeVerticies(writer, verticies, ids);
writeEdges(writer, edges, ids);
writer.write(CLOSE_LIST);
}
private void writeMapProperty(Writer writer, Map<?, ?> map, int tabs) throws IOException {
writer.write(OPEN_LIST);
tabs++;
for (Entry<?, ?> entry : map.entrySet()) {
writeTabs(writer, tabs);
writeKey(writer, entry.getKey().toString());
writeProperty(writer, entry.getValue(), tabs);
}
writeTabs(writer, tabs - 1);
writer.write(CLOSE_LIST);
}
private void writeEdgeProperties(Writer writer, Edge e, Integer source, Integer target)
throws IOException {
writer.write(TAB);
writer.write(GMLTokens.EDGE);
writer.write(OPEN_LIST);
writeKey(writer, GMLTokens.SOURCE);
writeNumberProperty(writer, source);
writeKey(writer, GMLTokens.TARGET);
writeNumberProperty(writer, target);
writeKey(writer, GMLTokens.LABEL);
writeStringProperty(writer, e.getLabel());
writeEdgeProperties(writer, e);
writer.write(TAB);
writer.write(CLOSE_LIST);
}
/**
* Write the data in a Graph to a GML OutputStream.
*
* @param gMLOutputStream the GML OutputStream to write the Graph data to
* @throws java.io.IOException thrown if there is an error generating the GML data
*/
public void outputGraph(final OutputStream gMLOutputStream) throws IOException {
// ISO 8859-1 as specified in the GML documentation
Writer writer =
new BufferedWriter(new OutputStreamWriter(gMLOutputStream, Charset.forName("ISO-8859-1")));
List<Vertex> verticies = new ArrayList<Vertex>();
List<Edge> edges = new ArrayList<Edge>();
populateLists(verticies, edges);
if (normalize) {
LexicographicalElementComparator comparator = new LexicographicalElementComparator();
Collections.sort(verticies, comparator);
Collections.sort(edges, comparator);
}
writeGraph(writer, verticies, edges);
writer.flush();
writer.close();
}
private void writeKey(Writer writer, String command) throws IOException {
writer.write(TAB);
writer.write(TAB);
writer.write(command);
writer.write(DELIMITER);
}
private void writeStringProperty(Writer writer, Object string) throws IOException {
writer.write("\"");
writer.write(string.toString());
writer.write("\"");
writer.write(NEW_LINE);
}
private void writeNumberProperty(Writer writer, Number integer) throws IOException {
writer.write(integer.toString());
writer.write(NEW_LINE);
}
private void writeTabs(Writer writer, int tabs) throws IOException {
for (int i = 0; i <= tabs; i++) {
writer.write(TAB);
}
}