/**
* Basic Graph Visualization — code based on examples from Grappa 1.4
* by John Mocenigo
* http://www2.research.att.com/~john/Grappa/
*
* @author Scott Sanner (ssanner@gmail.com)
* @version 11/29/04
*
**/
package graph.gviz;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.URL;
import java.net.URLConnection;
import att.grappa.Graph;
import att.grappa.GrappaSupport;
import util.WinUNIX;
public class GraphFormat {
// Note 1: To redirect output from a Java Process use CMD on Widnows and /bin/sh on UNIX
// Note 2: If providing direct I/O to Process, make sure to close input stream when done,
// otherwise process never exits!
public static boolean FormatGraphRedirectIO(String file_in, String file_out) {
try {
System.out.println(“Executing: ‘” + WinUNIX.GVIZ_CMD + ” ” + file_in + ” > ” + file_out + WinUNIX.GVIZ_CMD_CLOSE + “‘”);
Process p = Runtime.getRuntime().exec(WinUNIX.GVIZ_CMD + ” ” + file_in + ” > ” + file_out + WinUNIX.GVIZ_CMD_CLOSE);
System.out.print(“Waiting for graphviz to finish… “);
p.waitFor();
System.out.println(“done.”);
return true;
} catch (InterruptedException ie) {
System.out.println(ie);
return false;
} catch (IOException ioe) {
System.out.println(ioe);
return false;
}
}
// Make sure to close input stream so process exits! Could use readLine()
// in place of byte buffer but need to make sure final output is a newline!
public static boolean FormatGraphStreams(String file_in, String file_out) {
try {
byte[] buffer = new byte[65536];
// Open files for reading and writing
FileInputStream fis = new FileInputStream(file_in);
FileOutputStream fos = new FileOutputStream(file_out);
BufferedReader fis_reader = new BufferedReader(new InputStreamReader(fis));
PrintWriter fos_writer = new PrintWriter(fos, true);
Process p = Runtime.getRuntime().exec(WinUNIX.GVIZ_EXE);
InputStream process_out = p.getInputStream();
PrintWriter process_in = new PrintWriter(p.getOutputStream(), true);
// Provide input to process (could come from any stream)
String line = null;
while ((line = fis_reader.readLine()) != null) {
process_in.println(line);
}
fis_reader.close();
process_in.close(); // Need to close input stream so process exits!!!
// Get output from process (can also be used by BufferedReader to get
// line-by-line… see how fis_reader is constructed).
int bytes_read = -1;
while ((bytes_read = process_out.read(buffer)) >= 0) {
String temp_str = new String(buffer, 0, bytes_read);
fos_writer.print(temp_str);
System.out.print(temp_str);
}
process_out.close();
fos_writer.close();
System.out.print(“Waiting for graphviz to finish… “);
p.waitFor();
System.out.println(“done.”);
return true;
} catch (InterruptedException ie) {
System.out.println(ie);
return false;
} catch (IOException ioe) {
System.out.println(ioe);
return false;
}
}
// Note: This is really convoluted… should note how the Applet
// directly loads the formatted graph and do something similar
// here. -SPS
public static void LayoutGraph(Graph g) {
System.out.print(“\nPerforming graph layout… “);
Object connector = null;
try {
//System.out.println(“Trying local”);
if (g.isDirected())
connector = Runtime.getRuntime().exec(WinUNIX.GVIZ_EXE);
else
connector = Runtime.getRuntime().exec(WinUNIX.GVIZ2_EXE);
} catch(Exception ex) {
System.err.println(“Exception while setting up Process: ” +
ex.getMessage() +
“\nTrying format via URLConnection…”);
connector = null;
}
if(connector == null) {
try {
//System.out.println(“Trying URL”);
connector = (new URL(“http://www.research.att.com/~john/cgi-bin/format-graph”)).openConnection();
URLConnection urlConn = (URLConnection)connector;
urlConn.setDoInput(true);
urlConn.setDoOutput(true);
urlConn.setUseCaches(false);
urlConn.setRequestProperty(“Content-Type”,”application/x-www-form-urlencoded”);
} catch(Exception ex) {
System.err.println(“Exception while setting up URLConnection: ” + ex.getMessage() + “\nLayout not performed.”);
connector = null;
}
}
if(connector != null) {
if(!GrappaSupport.filterGraph(g,connector)) {
System.err.println(“ERROR: somewhere in filterGraph”);
}
if(connector instanceof Process) {
try {
int code = ((Process)connector).waitFor();
if(code != 0) {
System.err.println(“WARNING: proc exit code is: ” + code);
}
} catch(InterruptedException ex) {
System.err.println(“Exception while closing down proc: ” + ex.getMessage());
ex.printStackTrace(System.err);
}
}
connector = null;
} else {
System.out.println(“Could not access local or web-based graph layout.”);
System.exit(1);
}
System.out.println(“DONE”);
}
public static void main(String[] args) {
GraphFormat.FormatGraphRedirectIO(“ssanner_graph.dot.unformat”, “ssanner_graph.dot”);
}
}