Free: A Java Doclet Producing Inheritance GIFs Using Graphviz's Dot tool

In the last three hours I wrote this doclet -- a javadoc plugin. This
doclet generates a GIF image for each package. The GIF image shows the
inheritance tree for all types in package. There is one mandatory
parameter to doclet: the root directory where to put generated dot
files and gif files. I suspect that this is etiher the source root or
compiled classes root or a documentaiton root. The source assumes a
location for Graphviz's dot tool. For this doclet to work in a
different environment the location of Graphviz's dot tool may need to
be changed.

Here is the doclet class:

import com.sun.javadoc.*;
import java.io.*;
import java.util.*;

public class DotInheritance {
  private static final String dotexe =
    "c:\\graphviz\\Graphviz\\bin\\dot " +
    "-Tgif inheritance.dot -o inheritance.gif";
  public static boolean start(RootDoc root) {
    String outputtree = readOptions(root.options());
    PackageDoc packs[] = root.specifiedPackages();
    for (int i=0; i<packs.length; i++) {
      String packname = ""+packs[i];
      String packdir = packname.replace(".", File.separator );
      ClassDoc classes[] = packs[i].allClasses(false);
      File output = new File(outputtree,
        packdir+File.separator+"inheritance.dot");
      //System.out.println(""+output);
      if (makeDotFile(output, classes))
        makeGifFile(output);
    }
    return true;
  }
  private static class NodeWriter extends PrintStream {
     HashMap<Type, String> names = new HashMap();
     int index = 0;
     NodeWriter(FileOutputStream fos) {
       super(fos);
     }
     private String getName(Type t) {
       if (!names.containsKey(t)) {
         index++;
         String name = "c"+index;
         String modstr = "";
         if (t instanceof ProgramElementDoc)
           modstr = ((ProgramElementDoc)t).modifiers() + "\\n";
         println(" "+name+" [shape=box,label=\""+modstr+t+"\"]");
         names.put(t,name);
       }
       return names.get(t);
     }
     void connect(Type superType, Type subType) {
       String supername = getName(superType);
       String subname = getName(subType);
       println(" "+supername+" -> "+subname);
     }
     void assureShown(Type t) {
       getName(t);
     }
  }
  private static boolean makeDotFile(File out, ClassDoc classes[]) {
    boolean success = true;
    try {
      NodeWriter writer = new NodeWriter(new FileOutputStream(out));
      writer.println("digraph inheritance {");
      // writer.println(" size = \"11,8\" ");
      for (int i=0; i<classes.length; i++) {
        writer.assureShown(classes[i]);
        Type superType = classes[i].superclassType();
        if (superType!=null &&
!"java.lang.Object".equals(""+superType))
          writer.connect(superType, classes[i]);
        for (Type t: classes[i].interfaceTypes()) {
          writer.connect(t,classes[i]);
        }
      }
      writer.println("}");
      writer.close();
    } catch (IOException e) {
      System.err.println("Failed creating " + out);
      success = false;
    }
    return success;
  }
  private static void makeGifFile(File out) {
    Runtime runtime = Runtime.getRuntime();
    try {
      Process proc = runtime.exec(dotexe,null,out.getParentFile());
      if (proc.waitFor() != 0) {
        System.err.println("Failed making gif of " + out);
      }
    } catch (InterruptedException e) {
      System.err.println(e);
    } catch (IOException e) {
      System.err.println(e);
    }
  }
  private static final String outdirtag = "-output_directory_tree";
  public static int optionLength(String option) {
    if (option.equals(outdirtag)) {
      return 2;
    }
    return 0;
  }
  public static boolean validOptions(String options[][],
    DocErrorReporter reporter) {
    int noutdirtags = 0;
    for (int i = 0; i<options.length; i++) {
      String[] opt = options[i];
      if (opt[0].equals(outdirtag)) {
        noutdirtags++;
      } else {
        //System.out.println("unused option: "+opt[0]);
      }
    }
    switch (noutdirtags) {
      case 1:
        break;
      case 0:
      default:
        reporter.printError(
          "Usage: javadoc "+outdirtag+" $dir -doclet DotInheritance
....");
        break;
    }
    return noutdirtags==1;
  }
  private static String readOptions(String[][] options) {
    String tagValue = null;
    for (int i = 0; i < options.length; i++) {
      String[] opt = options[i];
      if (opt[0].equals(outdirtag)) {
        tagValue = opt[1];
      }
    }
    return tagValue;
  }

}

opalpa
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