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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。
- 配置文件的使用。(通过Properties加载配置文件)
- 动态调用其他的进程。(通过Runtime来实现)
- 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;/**
* <dl>
* <dt>Purpose: GraphViz Java API
* <dd>
*
* <dt>Description:
* <dd> With this Java class you can simply call dot
* from your Java programs.
* <dt>Example usage:
* <dd>
* <pre>
* 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 );
* </pre>
* </dd>
*
* </dl>
*
* @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 (<a href="jabba.laci@gmail.com">jabba.laci@gmail.com</a>)
*/
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 ChenaultString[] 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 toif( 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");}
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