将JBPM4调整到web工程

将JBPM4整合到web工程
1.在eclipse里面创建一个动态的web项目。

2.在lib目录下加入依赖库（由于我们在jsp中需要用到jstl标签，所以这里我们还必须加入jstl的依赖库）

引用

*JBPM4_HOME/jbpm.jar
*JBPM4_HOME/lib/*.jar
*jakarta-taglibs-standard-1.1.2_HOME/lib/jstl.jar
*jakarta-taglibs-standard-1.1.2_HOME/lib/standard.jar

用tomcat6页面会报错，
解决方法：

方法一：换成tomcat5.5 一点问题也没有了

方法二：将juel.jar, juel-engine.jar, juel-impl.jar这三个包复制到tomcat6下lib中，并删除原来的el-api.jar，切记要把WEB-INF\lib中的juel.jar, juel-engine.jar, juel-impl.jar删除。不然还是要冲突。


3.在项目的Java Resources目录下创建一个resources目录，并且把“JBPM4初探---HelloWorld”项目中src目录下的所有配置文件拷到resources目录下。

4.在项目的src目录一个java文件（servlet），用来编写我们发布流程并获取最新发布的流程定义

package com.test;   
  
import java.io.IOException;   
import java.util.ArrayList;   
import java.util.LinkedHashMap;   
import java.util.List;   
import java.util.Map;   
  
import javax.servlet.ServletConfig;   
import javax.servlet.ServletException;   
import javax.servlet.http.HttpServlet;   
import javax.servlet.http.HttpServletRequest;   
import javax.servlet.http.HttpServletResponse;   
  
import org.jbpm.api.Configuration;   
import org.jbpm.api.ProcessDefinition;   
import org.jbpm.api.ProcessDefinitionQuery;   
import org.jbpm.api.ProcessEngine;   
import org.jbpm.api.RepositoryService;   
  
public class JbpmServlet extends HttpServlet {   
    private static final long serialVersionUID = 1L;   
    private ProcessEngine processEngine = null;   
    private RepositoryService repositoryService = null;   
  
    /* 初始化ProcessEngine. */  
    public void init(ServletConfig config) throws ServletException {   
        processEngine = new Configuration().buildProcessEngine();   
        repositoryService = processEngine.getRepositoryService();   
    }   
  
    protected void doGet(HttpServletRequest request,   
            HttpServletResponse response) throws ServletException, IOException {   
        process(request, response);   
    }   
  
    protected void doPost(HttpServletRequest request,   
            HttpServletResponse response) throws ServletException, IOException {   
        process(request, response);   
    }   
  
    protected void process(HttpServletRequest request,   
            HttpServletResponse response) throws ServletException, IOException {   
        String zzg = request.getParameter("zzg");   
        if (zzg.equals("deploy")) {   
            deployProcessDefinition(request, response);   
        } else {   
            removeProcessDefinitionById(request, response);   
        }   
        List list = getLatestProcessDefinition(request, response);   
        request.setAttribute("process", list);   
        request.getRequestDispatcher("/index.jsp").forward(request, response);   
    }   
  
    /**  
     * 发布流程方法  
     * @param request  
     * @param response  
     * @throws ServletException  
     * @throws IOException  
     */  
    protected void deployProcessDefinition(HttpServletRequest request,   
            HttpServletResponse response) throws ServletException, IOException {   
        String xml = request.getParameter("xml");   
        repositoryService.createDeployment().addResourceFromString(   
                "hello.jpdl.xml", xml).deploy();   
    }   
  
    /* 获取所有最新流程. */  
    protected List<ProcessDefinition> getLatestProcessDefinition(   
            HttpServletRequest request, HttpServletResponse response)   
            throws ServletException, IOException {   
        //获取全部的流程定义   
        List<ProcessDefinition> processDefinitions = repositoryService   
                .createProcessDefinitionQuery().orderAsc(   
                        ProcessDefinitionQuery.PROPERTY_NAME).list();   
           
        Map<String, ProcessDefinition> map = new LinkedHashMap<String, ProcessDefinition>();   
        for (ProcessDefinition pd : processDefinitions) {   
            String key = pd.getKey();   
            ProcessDefinition definition = map.get(key);   
            if ((definition == null)   
                    || (definition.getVersion() < pd.getVersion())) {   
                map.put(key, pd);   
            }   
        }   
        return new ArrayList(map.values());   
    }   
  
    /* 删除流程定义. */  
    protected void removeProcessDefinitionById(HttpServletRequest request,   
            HttpServletResponse response) throws ServletException, IOException {   
        String id = request.getParameter("id");   
                //根据流程ID获取流程定义实例   
                //注意:jbpm4是不允许直接根据流程定义的ID来直接删除流程定义的   
        ProcessDefinition pd = repositoryService.createProcessDefinitionQuery()   
                .processDefinitionId(id).uniqueResult();   
  
        repositoryService.deleteDeploymentCascade(pd.getDeploymentId());   
    }   
}  

}


5.在项目的webapp目录建立一个index.jsp，主要用来发布流程并显示最新发布的流程

<%@page contentType="text/html;charset=UTF-8" %>   
<%@page import="org.jbpm.api.*" %>   
<%@page import="java.util.*" %>   
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>   
  
<html>   
    <head>   
        <title>jbpm学习</title>   
    </head>   
    <body>   
        <form action="jbpm?zzg=deploy" method="post">   
            <textarea name="xml" cols=50 rows=15></textarea>   
            <input type="submit" value="发布"/>   
            <input type="reset" value="取消"/>   
        </form>   
        <table width=430 border=1>   
            <tr>   
                <td>ID</td>   
                <td>Key</td>   
                <td>名称</td>   
                <td>版本</td>   
                <td>操作</td>   
            </tr>   
            <c:forEach var="process" items="${process}">   
            <tr>   
                <td>${process.id}</td>   
                <td>${process.key}</td>   
                <td>${process.name}</td>   
                <td>${process.version}</td>   
                <td><a href="jbpm?zzg=delete&id=${process.id }">删除</a></td>   
            </tr>   
            </c:forEach>   
        </table>   
    </body>   
</html>  

6.修改项目下的web.xml文件

 
    <servlet>   
        <description />   
        <servlet-name>JbpmServlet</servlet-name>   
        <servlet-class>com.test.JbpmServlet</servlet-class>   
    </servlet>   
    <servlet-mapping>   
        <servlet-name>JbpmServlet</servlet-name>   
        <url-pattern>/jbpm</url-pattern>   
    </servlet-mapping>   

7.为项目创建一个服务器,做测试。
在文本框中输入：

<?xml version="1.0" encoding="UTF-8"?>

<process name="hello" xmlns="http://jbpm.org/4.3/jpdl">
   <start g="235,38,48,48" name="start1">
      <transition name="to state1" to="state1" g="-59,-17"/>
   </start>
   <state g="214,154,92,52" name="state1">
      <transition name="to end1" to="end1" g="-47,-17"/>
   </state>
   <end g="240,284,48,48" name="end1"/>
</process>

如果没报错，测试成功。