为什么根据网上的教程配了后：
在jbpm_taskinstance表中会有两条记录。
其中的第二条记录，时间与第一条一致，但是数据记录中的actorid字段是null

跟踪了一下相关的输出SQL：
打印了是两条insert into jbpm_taskinstance记录

但是service层中的工作流的保存的地方确只进行了一次;

配置文件是这样的：
jbpm.cfg.xml:放置在了classpath下了：

 <jbpm-context>
    <service name="persistence">  
          <factory>  
              <bean class="org.jbpm.persistence.db.DbPersistenceServiceFactory">  
              	<field name="isTransactionEnabled"><false/></field>  
                <field name="isCurrentSessionEnabled"><true/></field>
              </bean>  
         </factory>  
    </service> 
    <service name="message" factory="org.jbpm.msg.db.DbMessageServiceFactory" />
    <service name="scheduler" factory="org.jbpm.scheduler.db.DbSchedulerServiceFactory" />
    <service name="logging" factory="org.jbpm.logging.db.DbLoggingServiceFactory" />
    <service name="authentication" factory="org.jbpm.security.authentication.DefaultAuthenticationServiceFactory" />
  </jbpm-context>

spring配置文件：

	<bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
		<property name="dataSource" ref="dataSource" />
		<property name="namingStrategy">
			<bean class="org.hibernate.cfg.ImprovedNamingStrategy" />
		</property>
		<property name="mappingLocations">  
            <list>          
                <!-- jbpm's hbm.xml -->  
                    <value>classpath*:/org/jbpm/**/*.hbm.xml</value>  
                <!-- other hbm.xml -->          
            </list>  
        </property>  
		<property name="hibernateProperties">
			<props>
				<prop key="hibernate.dialect">org.hibernate.dialect.MySQLInnoDBDialect</prop>
				<prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
				<prop key="hibernate.cache.provider_class">org.hibernate.cache.EhCacheProvider</prop>
				<prop key="hibernate.cache.use_query_cache">${hibernate.cache.use_query_cache}</prop>
				<prop key="hibernate.jdbc.batch_size">50</prop>
				<!-- <prop key="hibernate.cache.provider_configuration_file_resource_path">${hibernate.ehcache_config_file}</prop> -->
				<prop key="hibernate.generate_statistics">true</prop>
				<prop key="hibernate.connection.release_mode">
					auto
				</prop>

				<prop key="hibernate.autoReconnect">true</prop>
				<prop key="hibernate.cglib.use_reflection_optimizer">
					true
				</prop>
			</props>
		</property>
		<property name="packagesToScan" value="com.sdcncsi.entity.*" />
	</bean>

	   <bean id="jbpmConfiguration" class="org.springmodules.workflow.jbpm31.LocalJbpmConfigurationFactoryBean">  
        <property name="sessionFactory" ref="sessionFactory" />  
        <property name="configuration" value="classpath:/jbpm.cfg.xml" />  
        <!-- 第一处需要注意的地方 -->  
        <!--  <property name="processDefinitions">  -->
          <!--   <list>   增加新流程定义在下面 -->
            <!--     <ref local="testWorkflow" />  -->
          <!--   </list>  -->
        <!-- </property>  
         <property name="createSchema" value="false" /> 
        -->
       
        
    </bean>  
   <bean id="testWorkflow"  
        class="org.springmodules.workflow.jbpm31.definition.ProcessDefinitionFactoryBean">  
        <!-- property name="definitionLocation" value="classpath:testspring/processdefinition.xml" /> -->  
        <!-- <property name="definitionLocation" value="classpath:audit/auditCheck/processdefinition.xml" /> -->
        <property name="definitionLocation" value="classpath:zfcg/processdefinition.xml" />  
    </bean>  
   <bean id="flowUtils" class="com.sdcncsi.common.FlowUtils">  
   </bean>  
   <bean id="jbpmTemplate"  
        class="org.springmodules.workflow.jbpm31.JbpmTemplate">  
        <constructor-arg index="0" ref="jbpmConfiguration" />  
        <constructor-arg index="1" ref="testWorkflow" />  
    </bean>  

service层调用：

				JbpmContext jctx = jbpmTemplate.getJbpmConfiguration().createJbpmContext();
				ProcessDefinition pdf = jctx.getGraphSession().findLatestProcessDefinition("lcgy");
				pi = new ProcessInstance(pdf);
				pi.getContextInstance().setVariable("processer", nextProcesser);
				pi.getContextInstance().setVariable("jobs", Struts2Utils.getRequest().getAttribute("jobs"));
				pi.getContextInstance().setVariable("ins_id", pi.getId());
				System.out.println("------------------------"+nextProcesser);
				pi.signal();

大家都没有碰到过这问题是不是啊？