processimageservlet.java

workflow first jbpm

package com.yuyanshan.servlet;

import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.jbpm.JbpmConfiguration;
import org.jbpm.JbpmContext;
import org.jbpm.graph.def.ProcessDefinition;
import org.springframework.context.ApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
//import org.springframework.context.ApplicationContext;
//import org.springframework.web.context.support.WebApplicationContextUtils;

public class ProcessImageServlet extends HttpServlet {

	private static final long serialVersionUID = 1L;

	protected void doGet(HttpServletRequest request, HttpServletResponse response) 
	    throws ServletException, IOException {
    long processDefinitionId = Long.parseLong( request.getParameter( "definitionId" ) );
//    JbpmConfiguration jbpmConfiguration = JbpmConfiguration
//	.getInstance();   
    ApplicationContext ctx=WebApplicationContextUtils.getRequiredWebApplicationContext(request.getSession().getServletContext());
    JbpmConfiguration jbpmConfiguration=(JbpmConfiguration) ctx.getBean("jbpmConfiguration");
    JbpmContext jbpmContext =jbpmConfiguration.getCurrentJbpmContext();
    if(jbpmContext==null)
    {
    	jbpmContext=jbpmConfiguration.createJbpmContext();
    }
    ProcessDefinition processDefinition = jbpmContext.getGraphSession().loadProcessDefinition(processDefinitionId);
    byte[] bytes = processDefinition.getFileDefinition().getBytes("processimage.jpg");
    OutputStream out = response.getOutputStream();
    out.write(bytes);
    out.flush();

}
}