Graphviz JAVA API

转载自： java程序怎么调用Graphviz

java可以直接调用这个类实现画图功能，但是使用这个类的前提是你的电脑已经装了GraphViz软件，你可以在http://www.graphviz.org/Gallery.php下载windows版本，装完后，找到dot.exe所在的路径，我电脑上的是D:\Program Files\Graphviz2.30\bin\dot.exe,
将GraphViz.java中的这一路径改成你电脑上的路径，基本上就可以用了。
 
package Graphoutput;
// GraphViz.java - a simple API to call dot from Java programs
/*$Id$*/
/*
 ******************************************************************************
 *                                                                            *
 *              (c) Copyright 2003 Laszlo Szathmary                           *
 *                                                                            *
 * This program is free software; you can redistribute it and/or modify it    *
 * under the terms of the GNU Lesser General Public License as published by   *
 * the Free Software Foundation; either version 2.1 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 Lesser General Public    *
 * License for more details.                                                  *
 *                                                                            *
 * You should have received a copy of the GNU Lesser General Public License   *
 * along with this program; if not, write to the Free Software Foundation,    *
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.                              *
 *                                                                            *
 ******************************************************************************
 */

import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.InputStreamReader;

/**
 * 

 * 
Purpose: GraphViz Java API
 * 

 *
 * 
Description:
 * 
 With this Java class you can simply call dot
 *      from your Java programs
 * 
Example usage:
 * 

 * 
 *    GraphViz gv = new GraphViz();
 *    gv.addln(gv.start_graph());
 *    gv.addln("A -> B;");
 *    gv.addln("A -> C;");
 *    gv.addln(gv.end_graph());
 *    System.out.println(gv.getDotSource());
 *
 *    String type = "gif";
 *    File out = new File("out." + type);   // out.gif in this example
 *    gv.writeGraphToFile( gv.getGraph( gv.getDotSource(), type ), out );
 * 
 * 
 *
 * 
 *
 * @version v0.4, 2011/02/05 (February) -- Patch of Keheliya Gallaba is added. Now you
 * can specify the type of the output file: gif, dot, fig, pdf, ps, svg, png, etc.
 * @version v0.3, 2010/11/29 (November) -- Windows support + ability 
 * to read the graph from a text file
 * @version v0.2, 2010/07/22 (July) -- bug fix
 * @version v0.1, 2003/12/04 (December) -- first release
 * @author  Laszlo Szathmary ([email protected])
 */
public class GraphViz
{
   /**
    * The dir. where temporary files will be created.
    */
   //private static String TEMP_DIR = "/tmp"; // Linux
   private static String TEMP_DIR = "c:/temp"; // Windows

/**
    * Where is your dot program located? It will be called externally.
    */
  // private static String DOT = "/usr/bin/dot"; // Linux
   private static String DOT = "D:\\Program Files\\Graphviz2.30\\bin\\dot.exe"; // Windows

/**
    * The source of the graph written in dot language.
    */
 private StringBuilder graph = new StringBuilder();

/**
    * Constructor: creates a new GraphViz object that will contain
    * a graph.
    */
   public GraphViz() {
   }

/**
    * Returns the graph's source description in dot language.
    * @return Source of the graph in dot language.
    */
   public String getDotSource() {
      return graph.toString();
   }

/**
    * Adds a string to the graph's source (without newline).
    */
   public void add(String line) {
      graph.append(line);
   }

/**
    * Adds a string to the graph's source (with newline).
    */
   public void addln(String line) {
      graph.append(line + "\n");
   }

/**
    * Adds a newline to the graph's source.
    */
   public void addln() {
      graph.append('\n');
   }

/**
    * Returns the graph as an image in binary format.
    * @param dot_source Source of the graph to be drawn.
    * @param type Type of the output image to be produced, e.g.: gif, dot, fig, pdf, ps, svg, png.
    * @return A byte array containing the image of the graph.
    */
   public byte[] getGraph(String dot_source, String type)
   {
      File dot;
      byte[] img_stream = null;
   
      try {
         dot = writeDotSourceToFile(dot_source);
         if (dot != null)
         {
            img_stream = get_img_stream(dot, type);
            if (dot.delete() == false) 
               System.err.println("Warning: " + dot.getAbsolutePath() + " could not be deleted!");
            return img_stream;
         }
         return null;
      } catch (java.io.IOException ioe) { return null; }
   }

/**
    * Writes the graph's image in a file.
    * @param img   A byte array containing the image of the graph.
    * @param file  Name of the file to where we want to write.
    * @return Success: 1, Failure: -1
    */
   public int writeGraphToFile(byte[] img, String file)
   {
      File to = new File(file);
      return writeGraphToFile(img, to);
   }

/**
    * Writes the graph's image in a file.
    * @param img   A byte array containing the image of the graph.
    * @param to    A File object to where we want to write.
    * @return Success: 1, Failure: -1
    */
   public int writeGraphToFile(byte[] img, File to)
   {
      try {
         FileOutputStream fos = new FileOutputStream(to);
         fos.write(img);
         fos.close();
      } catch (java.io.IOException ioe) { ioe.printStackTrace();return -1; }
      return 1;
   }

/**
    * It will call the external dot program, and return the image in
    * binary format.
    * @param dot Source of the graph (in dot language).
    * @param type Type of the output image to be produced, e.g.: gif, dot, fig, pdf, ps, svg, png.
    * @return The image of the graph in .gif format.
    */
   private byte[] get_img_stream(File dot, String type)
   {
      File img;
      byte[] img_stream = null;

try {
         img = File.createTempFile("graph_", "."+type, new File(GraphViz.TEMP_DIR));
         Runtime rt = Runtime.getRuntime();
         
         // patch by Mike Chenault
         String[] args = {DOT, "-T"+type, dot.getAbsolutePath(), "-o", img.getAbsolutePath()};
         Process p = rt.exec(args);
         
         p.waitFor();

FileInputStream in = new FileInputStream(img.getAbsolutePath());
         img_stream = new byte[in.available()];
         in.read(img_stream);
         // Close it if we need to
         if( in != null ) in.close();

if (img.delete() == false) 
            System.err.println("Warning: " + img.getAbsolutePath() + " could not be deleted!");
      }
      catch (java.io.IOException ioe) {
         System.err.println("Error:    in I/O processing of tempfile in dir " + GraphViz.TEMP_DIR+"\n");
         System.err.println("       or in calling external command");
         ioe.printStackTrace();
      }
      catch (java.lang.InterruptedException ie) {
         System.err.println("Error: the execution of the external program was interrupted");
         ie.printStackTrace();
      }

return img_stream;   }
   /**
    * Writes the source of the graph in a file, and returns the written file
    * as a File object.
    * @param str Source of the graph (in dot language).
    * @return The file (as a File object) that contains the source of the graph.
    */
   public File writeDotSourceToFile(String str) throws java.io.IOException
   {
      File temp;
      try {
         temp = File.createTempFile("graph_", ".dot.tmp", new File(GraphViz.TEMP_DIR));
         FileWriter fout = new FileWriter(temp);
         fout.write(str);
         fout.close();
      }
      catch (Exception e) {
         System.err.println("Error: I/O error while writing the dot source to temp file!");
         return null;
      }
      return temp;
   }

/**
    * Returns a string that is used to start a graph.
    * @return A string to open a graph.
    */
   public String start_graph() {
      return "digraph G {" ;
   }

/**
    * Returns a string that is used to end a graph.
    * @return A string to close a graph.
    */
   public String end_graph() {
      return "}";
   }

/**
    * Read a DOT graph from a text file.
    * 
    * @param input Input text file containing the DOT graph
    * source.
    */
   public void readSource(String input)
   {
    StringBuilder sb = new StringBuilder();
    
    try
    {
     FileInputStream fis = new FileInputStream(input);
     DataInputStream dis = new DataInputStream(fis);
     BufferedReader br = new BufferedReader(new InputStreamReader(dis));
     String line;
     while ((line = br.readLine()) != null) {
      sb.append(line);
     }
     dis.close();
    } 
    catch (Exception e) {
     System.err.println("Error: " + e.getMessage());
    }
    
    this.graph = sb;
   }
   
} // end of class GraphViz

通过下面这个类调用graphViz.java
 
import java.io.File;
public class Proba
{
   public static void main(String[] args)
   {
      Proba p = new Proba();
      p.start();
//      p.start2();
   }

/**
    * Construct a DOT graph in memory, convert it
    * to image and store the image in the file system.
    */
   private void start()
   {
      GraphViz gv = new GraphViz();
      gv.addln(gv.start_graph());
      gv.addln("A -> B;");
      gv.addln("A -> C;");
      gv.addln(gv.end_graph());
      System.out.println(gv.getDotSource());
      
      String type = "gif";
//      String type = "dot";
//      String type = "fig";    // open with xfig
//      String type = "pdf";
//      String type = "ps";
//      String type = "svg";    // open with inkscape
//      String type = "png";
//      String type = "plain";
      File out = new File("/tmp/out." + type);   // Linux
//      File out = new File("c:/eclipse.ws/graphviz-java-api/out." + type);    // Windows
      gv.writeGraphToFile( gv.getGraph( gv.getDotSource(), type ), out );
   }
   
   /**
    * Read the DOT source from a file,
    * convert to image and store the image in the file system.
    */
   private void start2()
   {
 //     String dir = "/home/jabba/eclipse2/laszlo.sajat/graphviz-java-api";     // Linux
 //     String input = dir + "/sample/simple.dot";
    String input = "c:/eclipse.ws/graphviz-java-api/sample/simple.dot";    // Windows
    
    GraphViz gv = new GraphViz();
    gv.readSource(input);
    System.out.println(gv.getDotSource());
     
      String type = "gif";
//    String type = "dot";
//    String type = "fig";    // open with xfig
//    String type = "pdf";
//    String type = "ps";
//    String type = "svg";    // open with inkscape
//    String type = "png";
//      String type = "plain";
    File out = new File("/tmp/simple." + type);   // Linux
//    File out = new File("c:/eclipse.ws/graphviz-java-api/tmp/simple." + type);   // Windows
    gv.writeGraphToFile( gv.getGraph( gv.getDotSource(), type ), out );
   }
}