4

我试图让一个简单的 Spring 示例与 Activiti 5.5 一起使用,但遇到了一些麻烦。我正在使用在 %activiti_home%/apps/apache-tomcat-6.0.32/webapps/activiti-rest 下配置了 activiti 的流程引擎。

我修改了 spring 配置文件,以便它包含我的自定义 spring 配置文件:

<import resource="classpath*:applicationContext*.xml"/> 

我将 applicationContext.xml 文件部署到 activiti-rest/WEB-INF/classes 文件夹。Activiti 启动正常,我在我的 bean 构造函数中看到 System.out.println,所以我知道我的 spring 配置正在被读取并且 bean 正在被构造。我为实现 JavaDelegate 的类创建了一个 spring bean,并将我的 bean 注入它,它总是出现空值。

这是我的弹簧配置:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx" 
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans 
       http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd">

    <bean id="myBean" class="org.bpmn.examples.MyBean"/>
    <bean id="taskBean" class="org.bpmn.examples.GetBeanTest">
            <property name="myBean" ref="myBean"/>
    </bean>
</beans>

这是我的豆:

package org.bpmn.examples;

import java.io.Serializable;

public class MyBean implements Serializable {

    public MyBean() {
        super();
        System.out.println("<========================== myBean ===========================>");
        System.out.println("<========================== myBean ===========================>");
        System.out.println("<========================== myBean ===========================>");
    }
    /**
     * 
     */
    private static final long serialVersionUID = -2867207654072787909L;
    Long id;
    String description;

    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }
    public String getDescription() {
        return description;
    }
    public void setDescription(String description) {
        this.description = description;
    }

}

这是我实现 JavaDelegate 的类:

package org.bpmn.examples;

import org.activiti.engine.delegate.DelegateExecution;
import org.activiti.engine.delegate.JavaDelegate;

public class GetBeanTest implements JavaDelegate {

    private MyBean myBean;

    @Override
    public void execute(DelegateExecution execution) throws Exception {
        if(myBean == null){
            System.out.println("Bean was null!");
        }else{
            System.out.println("Bean is valid!");
        }

    }

    public void setMyBean(MyBean myBean) {
        this.myBean = myBean;
    }
}

这一切对我来说似乎很简单,但是我认为问题在于 Activiti 没有在我的 JavaService 任务上调用的类中使用 spring bean,它正在创建一个新实例。

<?xml version="1.0" encoding="UTF-8"?>
<definitions xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:activiti="http://activiti.org/bpmn" xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI" xmlns:omgdc="http://www.omg.org/spec/DD/20100524/DC" xmlns:omgdi="http://www.omg.org/spec/DD/20100524/DI" typeLanguage="http://www.w3.org/2001/XMLSchema" expressionLanguage="http://www.w3.org/1999/XPath" targetNamespace="http://www.activiti.org/test">
  <process id="TestSpringConfig" name="TestSpringConfig">
    <documentation>Place documentation for the 'TestSpringConfig' process here.</documentation>
    <startEvent id="startevent1" name="Start"></startEvent>
    <serviceTask id="servicetask1" name="BeanTest" activiti:class="org.bpmn.examples.GetBeanTest"></serviceTask>
    <endEvent id="endevent1" name="End"></endEvent>
    <sequenceFlow id="flow1" name="" sourceRef="startevent1" targetRef="servicetask1"></sequenceFlow>
    <sequenceFlow id="flow2" name="" sourceRef="servicetask1" targetRef="endevent1"></sequenceFlow>
  </process>
</definitions>

如何获得对 Spring Bean 的引用,无论是像我这里有的简单的,还是已配置为 JPA 实体的?

任何/所有回复表示赞赏!


6.28.2011 更新:在尝试更改 activiti-rest 应用程序以使用 SpringProcessEngineConfiguration 而不是独立的 StandaloneProcessEngineConfiguration 时,我更改了 activiti-cfg.jar 文件中的 activiti-cfg.xml 文件并重新启动了 Tomcat。

我将 xml 文件更改为如下所示:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" 
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans   http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="dataSource" class="org.springframework.jdbc.datasource.SimpleDriverDataSource">
        <property name="driverClass" value="org.h2.Driver" />
        <property name="url" value="jdbc:h2:tcp://localhost/activiti" />
        <property name="username" value="sa" />
        <property name="password" value="" />
    </bean>

  <bean id="processEngineConfiguration" class="org.activiti.spring.SpringProcessEngineConfiguration"/>
  <bean id="processEngine" class="org.activiti.spring.ProcessEngineFactoryBean">
    <property name="processEngineConfiguration" ref="processEngineConfiguration" />
  </bean>

  <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
    <property name="dataSource" ref="dataSource" />
  </bean>

  <bean id="processEngineConfiguration" class="org.activiti.spring.SpringProcessEngineConfiguration">
    <property name="dataSource" ref="dataSource" />
    <property name="transactionManager" ref="transactionManager" />
    <property name="databaseSchemaUpdate" value="true" />
    <property name="jobExecutorActivate" value="false" />
  </bean>

  <bean id="processEngine" class="org.activiti.spring.ProcessEngineFactoryBean">
    <property name="processEngineConfiguration" ref="processEngineConfiguration" />
  </bean>

  <bean id="repositoryService" factory-bean="processEngine" factory-method="getRepositoryService" />
  <bean id="runtimeService" factory-bean="processEngine" factory-method="getRuntimeService" />
  <bean id="taskService" factory-bean="processEngine" factory-method="getTaskService" />
  <bean id="historyService" factory-bean="processEngine" factory-method="getHistoryService" />
  <bean id="managementService" factory-bean="processEngine" factory-method="getManagementService" />

</beans>

当我重新启动 Tomcat 时没有出现异常,但是当我打开资源管理器并尝试登录时,我得到以下异常:

INFO: Server startup in 12011 ms
10:32:02,338  ERROR [extensions.webscripts.AbstractRuntime] Exception from executeScript - redirecting to status template error: 05280000 Wrapped Exception (with status template): null
org.springframework.extensions.webscripts.WebScriptException: 05280000 Wrapped Exception (with status template): null
    at org.springframework.extensions.webscripts.AbstractWebScript.createStatusException(AbstractWebScript.java:742)
    at org.springframework.extensions.webscripts.DeclarativeWebScript.execute(DeclarativeWebScript.java:167)
4

3 回答 3

13

我的一个项目使用 Activiti 和 spring。我认为 JavaDelagate 可能是问题所在。您可以通过这种方式从每个spring bean的activiti的服务任务中调用:

豆定义:

<bean id="exampleBean" class="org.bpmn.examples.ExampleBean"/>

活动xml:

<serviceTask id="servicetask" name="Example" activiti:expression="${exampleBean.doSomething()}"></serviceTask>

您还可以将参数传递给函数,例如过程变量:

<serviceTask id="servicetask" name="Example" activiti:expression="${exampleBean.doSomething(processVariable)}"></serviceTask>

我总是以这种方式使用服务任务,并且没有遇到单例 bean 的问题。希望能帮助到你。如果我不明白您的问题,请发表评论。

更新:

我的项目像嵌入式工作流引擎一样使用 activiti。Activiti 使用与我的 webapp 相同的 applicationContext。

我的流程引擎配置:

<bean id="processEngineConfiguration" class="org.activiti.spring.SpringProcessEngineConfiguration">
        <property name="databaseType" value="mssql" />
        <property name="dataSource" ref="dataSource" />
        <property name="transactionManager" ref="transactionManager" />
        <property name="databaseSchemaUpdate" value="true" />
        <property name="jobExecutorActivate" value="true" />
        <property name="deploymentResources" value="classpath*:/diagrams/*.bpmn20.xml" />           
    </bean> 


    <bean id="processEngine" class="org.activiti.spring.ProcessEngineFactoryBean">
        <property name="processEngineConfiguration" ref="processEngineConfiguration" />
    </bean>
于 2011-06-28T08:18:11.200 回答
1

我正在使用@Autowired

引入我的依赖项。由于 Spring 没有实例化 JavaDelegate,因此我调用

applicationContext.getAutowireCapableBeanFactory().autowireBean(this);

在我的委托超类的构造函数中,它将所有依赖项注入到委托中。您可能想知道从哪里获取 applicationContext,http://sujitpal.blogspot.com/2007/03/accessing-spring-beans-from-legacy-code.html为您提供了答案。

于 2012-02-16T16:23:42.633 回答
0

我的猜测是,activiti 确实总是会创建一个新实例,因为 activiti 不知道它应该从 spring 容器中检索一个实例。

如果您尚未检查此资源:

http://www.activiti.org/userguide/index.html#springintegration

也许这就是你所需要的(即 ProcessEngineFactoryBean)

于 2011-06-24T22:54:47.967 回答