如何在web页面上显示shark的流程图

原理其实很简单，利用jawe将xpdl处理为jpeg，然后在页面上显示,
在web页面上显示shark的流程图的步骤：
1、写一个servlet,将流程在web页面上以图形的方式显示。代码如下：
package com.paiao.shark;

import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.PrintStream;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.*;
import org.enhydra.shark.Shark;
import org.enhydra.shark.api.client.wfservice.AdminInterface;
import org.enhydra.shark.api.client.wfservice.PackageAdministration;
import org.enhydra.shark.api.client.wfbase.*;
import java.io.*;

import org.enhydra.jawe.*;
import org.enhydra.jawe.graph.Process;
import org.enhydra.jawe.xml.elements.Package;
import org.enhydra.jawe.xml.elements.WorkflowProcess;
import org.enhydra.jawe.xml.elements.WorkflowProcesses;
import java.util.Iterator;

public class ProcessImageServlet
    extends HttpServlet {
  private static boolean  _debug = false;
  private static final long serialVersionUID = 1L;
  private static final String CONTENT_TYPE = "text/html; charset=GBK";
  public void init() throws ServletException {
    System.out.println("init process image servlet");
    JaWEConfig conf = JaWEConfig.getInstance();
    conf.setBackgroundColor("Color.white");
    conf.setGridColor("Color.white");
    conf.setGenericActivityColor("Color.lightGray");
    conf.setActivityWidth(75);
    conf.setActivityHeight(40);
  }
  public void doGet(HttpServletRequest request, HttpServletResponse response) throws
      ServletException, IOException {
    try {
      String pkgId = request.getParameter("pkgId");
      String processId = request.getParameter("procId");
      String actSelect = request.getParameter("actId");
      AbstractGraph g = createImage(pkgId, processId);
      if (g != null) {
        if (actSelect != null && !actSelect.equals(""))
          selectCell(g, actSelect);
        response.setContentType("image/png");
        BufferedImage image = drawImage(g, true);
        ServletOutputStream out = response.getOutputStream();
        ImageIO.write(image, "png", out);
        out.flush();
        out.close();
      }
      else {
        System.err.println("g == null");
      }
    }
    catch (Exception e) {
      e.printStackTrace();
      return;
    }
  }
  public void doPost(HttpServletRequest request, HttpServletResponse response) throws
      ServletException, IOException {
    doGet(request, response);
  }
  public void destroy() {
  }
  private static AbstractGraph createImage(String pkgId, String processId) {
    if (pkgId == null || processId == null)
      return null;

       String filename="D:\\javatest\\sharkjspclient\\defaultroot\\repository\\external\\gaoli.xpdl";
       JaWE jawe=JaWE.getInstance();
       Package pkg=jawe.openDocument(filename,true,false);
       PackageEditor pkgEd=jawe.getPackageEditor();
       pkgEd.setNewPackage(pkg,true);
       WorkflowProcesses wps=(WorkflowProcesses)pkg.get("WorkflowProcesses");
       Iterator it=wps.toCollection().iterator();
       AbstractGraph currentGraph=null;
       while (it.hasNext()) {
         WorkflowProcess wp = (WorkflowProcess) it.next();
         Process p = pkgEd.getProcessObject(wp);
         AbstractEditor editor = p.getImplementationEditor();
         currentGraph = editor.getGraph();
         currentGraph.setSize(currentGraph.getPreferredSize());
       }
    return currentGraph;
  }
  public static String GBKToUTF(String strIn) {
    String strOut;
    strOut = null;
    if (strIn == null || strIn.trim().equals(""))
      return "";
    byte[] b = null;
    try {
      b = strIn.getBytes("GB2312");
      strOut = new String(b, "utf-8");
    }
    catch (UnsupportedEncodingException ex) {
    }
    return strOut;
  }
  public static String GBKToUTF(byte strIn[]) {
    String strOut;
    strOut = null;
    if (strIn == null)
      return "";
    try {
      strOut = new String(strIn, "utf-8");
    }
    catch (UnsupportedEncodingException ex) {
    }
    return strOut;
  }
  private static void selectCell(AbstractGraph graph, String activityId) {
    try {
      WorkflowManager wm = graph.getWorkflowManager();
      Object go = wm.getActivity(activityId);
      if (go != null)
        graph.addSelectionCell(go);
    }
    catch (Exception e) {
      System.err.println(e);
      return;
    }
  }
  private static BufferedImage drawImage(Component c, boolean resize) {
    if (resize)
      c.setSize(c.getPreferredSize());
    Dimension size = c.getSize();
    BufferedImage image = new BufferedImage(size.width - 50, size.height - 50,
                                            1);
    Graphics2D g2 = image.createGraphics();
    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                        RenderingHints.VALUE_ANTIALIAS_ON);
    g2.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
                        RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
    c.paint(g2);
    g2.dispose();
    return image;
  }
}
2、写一个调用servlet的jsp页面，代码如下：
<%@ page contentType="text/html; charset=GBK" %>
<%@ page language = "java" import="java.util.*" %>
<%@ page import="test.JSPClientUtilities" %>
<%
   String activityId = request.getParameter("activityId");
    String g_ContextPath = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+g_ContextPath+"/jsp/workflow/";
    String xpdl_process_id = "请假申请";
    String []array = JSPClientUtilities.getGraphpicParameter(activityId);
   String workflowOpeningUrl = g_ContextPath + "/jsp/workflow/ProcessImage.png?" +
      "pkgId=" + array[0] + "&" +
      "procId=" + array[1] + "&" +
      "actId=" + array[2];
    %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    <title><%=xpdl_process_id%>流程图</title>
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">
  </head>
  <body>
    <img src="<%=workflowOpeningUrl%>">
  </body>
</html>
3、在处理流程的页面上调用显示流程的jsp，要传一个当前活动的id，部分代码如下：
function viewproc(activatyId){
   window.open("/jsp/workflow/processImage.jsp?activityId="+activatyId,"查看流程信息","toolbar=no, status=no,menubar=no, scrollbars=yes,resizable=no,width=800,height=600,left=80,top=60");
}