Activiti Process Engine bean 未创建

Question

我的 spring-context.xml 文件

<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
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
http://www.springframework.org/schema/context 
http://www.springframework.org/schema/context/spring-context-2.5.xsd        
http://www.springframework.org/schema/tx      
http://www.springframework.org/schema/tx/spenter code herering-tx-3.0.xsd">

 <tx:annotation-driven transaction-manager="transactionManager"/>

<bean id="dataSource"
    class="org.springframework.jdbc.datasource.SimpleDriverDataSource">
    <property name="driverClass" value="org.postgresql.Driver" />
    <property name="url" value="jdbc:postgresql://localhost:5432/activiti_ex_db" />
    <property name="username" value="postgres" />
    <property name="password" value="user" />
</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="create-drop" />
    <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" />  -->

## Java 类

这是我的主程序

    import org.activiti.spring.ProcessEngineFactoryBean;
import org.springframework.context.support.ClassPathXmlApplicationContext;


    public class ActivitEx {

        public static void main(String[] args) {
            ClassPathXmlApplicationContext applicationContext = null;
            try {
                applicationContext = new ClassPathXmlApplicationContext("/spring-context.xml");
                ProcessEngineFactoryBean processEngin =(ProcessEngineFactoryBean) applicationContext.getBean("processEngine");
                System.out.println(processEngin);
            } catch (Exception e) {
                e.printStackTrace();
                applicationContext = null;
            }
        }       

    }

运行上述课程时出现以下错误。 你能帮忙吗..

错误

        May 17, 2016 7:20:35 PM org.activiti.engine.impl.interceptor.CommandContext close
SEVERE: Error while closing command context
java.lang.NullPointerException
    at org.activiti.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:42)
    at org.activiti.spring.SpringTransactionInterceptor$1.doInTransaction(SpringTransactionInterceptor.java:42)
    at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:130)
    at org.activiti.spring.SpringTransactionInterceptor.execute(SpringTransactionInterceptor.java:40)
    at org.activiti.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:33)
    at org.activiti.engine.impl.ProcessEngineImpl.<init>(ProcessEngineImpl.java:77)
    at org.activiti.engine.impl.cfg.ProcessEngineConfigurationImpl.buildProcessEngine(ProcessEngineConfigurationImpl.java:237)
    at org.activiti.spring.SpringProcessEngineConfiguration.buildProcessEngine(SpringProcessEngineConfiguration.java:60)
    at org.activiti.spring.ProcessEngineFactoryBean.getObject(ProcessEngineFactoryBean.java:56)
    at org.activiti.spring.ProcessEngineFactoryBean.getObject(ProcessEngineFactoryBean.java:32)
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:144)
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.getObjectFromFactoryBean(FactoryBeanRegistrySupport.java:103)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getObjectForBeanInstance(AbstractBeanFactory.java:1514)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:252)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:973)
    at Clint.main(Clint.java:9)

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'processEngine': FactoryBean threw exception on object creation; nested exception is java.lang.NullPointerException
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:151)
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.getObjectFromFactoryBean(FactoryBeanRegistrySupport.java:103)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getObjectForBeanInstance(AbstractBeanFactory.java:1514)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:252)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:973)
    at Clint.main(Clint.java:9)
Caused by: java.lang.NullPointerException
    at org.activiti.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:42)
    at org.activiti.spring.SpringTransactionInterceptor$1.doInTransaction(SpringTransactionInterceptor.java:42)
    at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:130)
    at org.activiti.spring.SpringTransactionInterceptor.execute(SpringTransactionInterceptor.java:40)
    at org.activiti.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:33)
    at org.activiti.engine.impl.ProcessEngineImpl.<init>(ProcessEngineImpl.java:77)
    at org.activiti.engine.impl.cfg.ProcessEngineConfigurationImpl.buildProcessEngine(ProcessEngineConfigurationImpl.java:237)
    at org.activiti.spring.SpringProcessEngineConfiguration.buildProcessEngine(SpringProcessEngineConfiguration.java:60)
    at org.activiti.spring.ProcessEngineFactoryBean.getObject(ProcessEngineFactoryBean.java:56)
    at org.activiti.spring.ProcessEngineFactoryBean.getObject(ProcessEngineFactoryBean.java:32)
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:144)
    ... 6 more

Answer 1

在processEngineConfiguration bean定义中，你可以通过改变下面的属性值来尝试

<property name="databaseSchemaUpdate" value="create-drop" />

到

<property name="databaseSchemaUpdate" value="true" />