java -- java中调用GraphViz

java – java中调用GraphViz

1.相关的代码

摘自：http://stackoverflow.com/questions/26481910/how-to-call-graphviz-from-java

一些前提知识：

• 利用GraphViz的命令行,在命令行窗口中使用。（dot -Tgif -o output.gif test2.dot）

下面编程中用到的一些技巧。

1. 配置文件的使用。（通过Properties加载配置文件）
2. 动态调用其他的进程。(通过Runtime来实现)
3. 临时文件的使用。（public static File createTempFile(String prefix,
   String suffix)在默认临时文件目录中创建一个空文件，使用给定前缀和后缀生成其名称。【临时目录必须提前存在，而不是此方法创建】）

1.1为GraphViz的java的API建立一个config.properties。

config.properties内容如下：

##############################################################
#                    Linux Configurations                    #
##############################################################
# The dir. where temporary files will be created.
tempDirForLinux = /tmp
# Where is your dot program located? It will be called externally.
dotForLinux = /usr/bin/dot

##############################################################
#                   Windows Configurations                   #
##############################################################
# The dir. where temporary files will be created.
tempDirForWindows7 = E:/temp
# Where is your dot program located? It will be called externally.
dotForWindows7 = "E:/software_daily/FOR_LEARN/graphViz/bin/dot.exe"

##############################################################
#                    Mac Configurations                      #
##############################################################
# The dir. where temporary files will be created.
tempDirForMacOSX = /tmp
# Where is your dot program located? It will be called externally.
dotForMacOSX = /usr/local/bin/dot

1.2 针对GraphViz写的API。（简单版本）

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

/**
* 

* 
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 v0.5.1, 2013/03/18 (March) -- Patch of Juan Hoyos (Mac support)
* @version v0.5, 2012/04/24 (April) -- Patch of Abdur Rahman (OS detection + start subgraph + 
* read config file)
* @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
{
 /**
  * Detects the client's operating system.
  */
 private final static String osName = System.getProperty("os.name").replaceAll("\\s","");

 /**
  * Load the config.properties file.
  */
 private final static String cfgProp = "config/config.properties";
 private final static Properties configFile = new Properties() {
     private final static long serialVersionUID = 1L; {
         try {
             load(new FileInputStream(cfgProp));
         } catch (Exception e) {}
     }
 };

 /**
  * The dir. where temporary files will be created.
  */
private static String TEMP_DIR = "test/tmpDir";

 /**
  * Where is your dot program located? It will be called externally.
  */
private static String DOT = configFile.getProperty("dotFor" + osName);

 /**
  * The image size in dpi. 96 dpi is normal size. Higher values are 10% higher each.
  * Lower values 10% lower each.
  * 
  * dpi patch by Peter Mueller
  */
 private int[] dpiSizes = {46, 51, 57, 63, 70, 78, 86, 96, 106, 116, 128, 141, 155, 170, 187, 206, 226, 249};

 /**
  * Define the index in the image size array.
  */
 private int currentDpiPos = 7;

 /**
  * Increase the image size (dpi).
  */
 public void increaseDpi() {
     if ( this.currentDpiPos < (this.dpiSizes.length - 1) ) {
         ++this.currentDpiPos;
     }
 }

 /**
  * Decrease the image size (dpi).
  */
 public void decreaseDpi() {
     if (this.currentDpiPos > 0) {
         --this.currentDpiPos;
     }
 }

 public int getImageDpi() {
     return this.dpiSizes[this.currentDpiPos];
 }

 /**
  * 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 this.graph.toString();
 }

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

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

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

 public void clearGraph(){
     this.graph = new StringBuilder();
 }

 /**
  * 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) { 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, "-Gdpi="+dpiSizes[this.currentDpiPos], 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.
  */
 private File writeDotSourceToFile(String str) throws java.io.IOException
 {
     File temp;
     try {
         temp = File.createTempFile("dorrr",".dot", new File(GraphViz.TEMP_DIR));
         FileWriter fout = new FileWriter(temp);
         fout.write(str);
                    BufferedWriter br=new BufferedWriter(new FileWriter("dotsource.dot"));
                    br.write(str);
                    br.flush();
                    br.close();
         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 "}";
 }

 /**
  * Takes the cluster or subgraph id as input parameter and returns a string
  * that is used to start a subgraph.
  * @return A string to open a subgraph.
  */
 public String start_subgraph(int clusterid) {
     return "subgraph cluster_" + clusterid + " {";
 }

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

1.3使用示例

下面这个为主要测试情况：

public static void createDotGraph(String dotFormat,String fileName)
{
    GraphViz gv=new GraphViz();
    gv.addln(gv.start_graph());
    gv.add(dotFormat);
    gv.addln(gv.end_graph());
   // String type = "gif";
    String type = "pdf";
  // gv.increaseDpi();
    gv.decreaseDpi();
    gv.decreaseDpi();
    File out = new File(fileName+"."+ type); 
    gv.writeGraphToFile( gv.getGraph( gv.getDotSource(), type ), out );
}

我们在main函数中调用上面的方法：

public static void main(String[] args) throws Exception {
        String dotFormat="1->2;1->3;1->4;4->5;4->6;6->7;5->7;3->8;3->6;8->7;2->8;2->5;";
        createDotGraph(dotFormat, "DotGraph");
 }