public SpringProcessEngineConfiguration processEngineConfigurationBean(Resource[] processDefinitions,
                                                                       DataSource dataSource,
                                                                       PlatformTransactionManager transactionManager,
                                                                       SpringAsyncExecutor springAsyncExecutor)
      throws IOException {

  SpringProcessEngineConfiguration engine = new SpringProcessEngineConfiguration();
  if (processDefinitions != null && processDefinitions.length > 0) {
    engine.setDeploymentResources(processDefinitions);
  }
  engine.setDataSource(dataSource);
  engine.setTransactionManager(transactionManager);

  if (null != springAsyncExecutor) {
    engine.setAsyncExecutor(springAsyncExecutor);
  }

  return engine;
}
 

/**
 * Ensure that the Activiti's thread pool uses the correct configuration value.
 * 
 * This assertion is limited in that the configuration values must be set before Spring application context is initialized, which we cannot control easily
 * in unit test.
 */
@Test
public void testActivitiThreadPoolUsesConfiguredValues()
{
    AsyncExecutor asyncExecutor = processEngineConfiguration.getAsyncExecutor();
    SpringAsyncExecutor springAsyncExecutor = (SpringAsyncExecutor) asyncExecutor;
    TaskExecutor taskExecutor = springAsyncExecutor.getTaskExecutor();
    ThreadPoolTaskExecutor threadPoolTaskExecutor = (ThreadPoolTaskExecutor) taskExecutor;

    Integer corePoolSize = threadPoolTaskExecutor.getCorePoolSize();
    Integer maxPoolSize = threadPoolTaskExecutor.getMaxPoolSize();
    Integer keepAliveSeconds = threadPoolTaskExecutor.getKeepAliveSeconds();
    // No real easy way of getting the queue capacity from the already constructed thread pool
    Integer remainingCapacity = ((LinkedBlockingQueue<?>) threadPoolTaskExecutor.getThreadPoolExecutor().getQueue()).remainingCapacity();

    assertEquals(configurationHelper.getProperty(ConfigurationValue.ACTIVITI_THREAD_POOL_CORE_POOL_SIZE, Integer.class), corePoolSize);
    assertEquals(configurationHelper.getProperty(ConfigurationValue.ACTIVITI_THREAD_POOL_MAX_POOL_SIZE, Integer.class), maxPoolSize);
    assertEquals(configurationHelper.getProperty(ConfigurationValue.ACTIVITI_THREAD_POOL_KEEP_ALIVE_SECS, Integer.class), keepAliveSeconds);
    assertEquals(configurationHelper.getProperty(ConfigurationValue.ACTIVITI_THREAD_POOL_QUEUE_CAPACITY, Integer.class), remainingCapacity);
}
 

@Bean
public SpringProcessEngineConfiguration springProcessEngineConfiguration(DataSource dataSource, PlatformTransactionManager transactionManager,
                                                                         SpringAsyncExecutor springAsyncExecutor
) throws IOException {
    SpringProcessEngineConfiguration engineConfiguration = baseSpringProcessEngineConfiguration(
            dataSource,
            transactionManager,
            springAsyncExecutor);
    Map<String, List<ActivitiEventListener>> typedListeners = new HashMap<>();
    typedListeners.put("TASK_CREATED", Collections.singletonList(taskCreatedListener()));
    typedListeners.put("TASK_COMPLETED", Collections.singletonList(taskCompletedListener()));
    engineConfiguration.setTypedEventListeners(typedListeners);
    return engineConfiguration;
}
 

@Bean
@ConditionalOnMissingBean
public SpringProcessEngineConfiguration springProcessEngineConfiguration(
        DataSource dataSource, EntityManagerFactory entityManagerFactory,
        PlatformTransactionManager transactionManager, SpringAsyncExecutor springAsyncExecutor) throws IOException {

  SpringProcessEngineConfiguration config = this.baseSpringProcessEngineConfiguration(dataSource, 
      transactionManager, springAsyncExecutor);
  config.setJpaEntityManagerFactory(entityManagerFactory);
  config.setTransactionManager(transactionManager);
  config.setJpaHandleTransaction(false);
  config.setJpaCloseEntityManager(false);
  return config;
}
 

@Bean
@ConditionalOnMissingBean
public SpringProcessEngineConfiguration springProcessEngineConfiguration(
        DataSource dataSource,
        PlatformTransactionManager transactionManager,
        SpringAsyncExecutor springAsyncExecutor) throws IOException {
  
  return this.baseSpringProcessEngineConfiguration(dataSource, transactionManager, springAsyncExecutor);
}
 

@Bean
public SpringProcessEngineConfiguration springProcessEngineConfiguration(
        @Qualifier("activitidatabaseSource") DataSource dataSource,
        @Qualifier("activitiTransactionManager") PlatformTransactionManager transactionManager,
        SpringAsyncExecutor springAsyncExecutor) throws IOException {
    return this.baseSpringProcessEngineConfiguration(dataSource, transactionManager, springAsyncExecutor);
}
 

/**
 * Ensure that the Activiti's thread pool is separate from the application's generic thread pool.
 */
@Test
public void testActivitiThreadPoolIsIsolatedFromGenericAsyncPool()
{
    AsyncExecutor asyncExecutor = processEngineConfiguration.getAsyncExecutor();
    SpringAsyncExecutor springAsyncExecutor = (SpringAsyncExecutor) asyncExecutor;
    TaskExecutor taskExecutor = springAsyncExecutor.getTaskExecutor();

    assertTrue(genericTaskExecutor != taskExecutor);
}
 

@Bean
public SpringAsyncExecutor springAsyncExecutor(TaskExecutor taskExecutor) {
  return new SpringAsyncExecutor(taskExecutor, springRejectedJobsHandler());
}
 

protected SpringProcessEngineConfiguration baseSpringProcessEngineConfiguration(DataSource dataSource, PlatformTransactionManager platformTransactionManager,
                                                                                SpringAsyncExecutor springAsyncExecutor) throws IOException {

  List<Resource> procDefResources = this.discoverProcessDefinitionResources(
      this.resourceLoader, this.activitiProperties.getProcessDefinitionLocationPrefix(),
      this.activitiProperties.getProcessDefinitionLocationSuffixes(),
      this.activitiProperties.isCheckProcessDefinitions());

  SpringProcessEngineConfiguration conf = super.processEngineConfigurationBean(
      procDefResources.toArray(new Resource[procDefResources.size()]), dataSource, 
      platformTransactionManager, springAsyncExecutor);

  conf.setDeploymentName(defaultText(activitiProperties.getDeploymentName(), conf.getDeploymentName()));
  conf.setDatabaseSchema(defaultText(activitiProperties.getDatabaseSchema(), conf.getDatabaseSchema()));
  conf.setDatabaseSchemaUpdate(defaultText(activitiProperties.getDatabaseSchemaUpdate(), conf.getDatabaseSchemaUpdate()));
  
  conf.setDbIdentityUsed(activitiProperties.isDbIdentityUsed());
  conf.setDbHistoryUsed(activitiProperties.isDbHistoryUsed());
  
  conf.setAsyncExecutorActivate(activitiProperties.isAsyncExecutorActivate());
  
  conf.setMailServerHost(activitiProperties.getMailServerHost());
  conf.setMailServerPort(activitiProperties.getMailServerPort());
  conf.setMailServerUsername(activitiProperties.getMailServerUserName());
  conf.setMailServerPassword(activitiProperties.getMailServerPassword());
  conf.setMailServerDefaultFrom(activitiProperties.getMailServerDefaultFrom());
  conf.setMailServerUseSSL(activitiProperties.isMailServerUseSsl());
  conf.setMailServerUseTLS(activitiProperties.isMailServerUseTls());
  
  conf.setHistoryLevel(activitiProperties.getHistoryLevel());

  if (activitiProperties.getCustomMybatisMappers() != null) {
    conf.setCustomMybatisMappers(getCustomMybatisMapperClasses(activitiProperties.getCustomMybatisMappers()));
  }

  if (activitiProperties.getCustomMybatisXMLMappers() != null) {
    conf.setCustomMybatisXMLMappers(new HashSet<String>(activitiProperties.getCustomMybatisXMLMappers()));
  }

  if (activitiProperties.getCustomMybatisMappers() != null) {
    conf.setCustomMybatisMappers(getCustomMybatisMapperClasses(activitiProperties.getCustomMybatisMappers()));
  }

  if (activitiProperties.getCustomMybatisXMLMappers() != null) {
    conf.setCustomMybatisXMLMappers(new HashSet<String>(activitiProperties.getCustomMybatisXMLMappers()));
  }
  
  if (processEngineConfigurationConfigurer != null) {
  	processEngineConfigurationConfigurer.configure(conf);
  }
  //从ActivitiEngineConfiguration copy来的
  FormEngineConfiguration formEngineConfiguration = new FormEngineConfiguration();
  formEngineConfiguration.setDataSource(dataSource);

  FormEngineConfigurator formEngineConfigurator = new FormEngineConfigurator();
  formEngineConfigurator.setFormEngineConfiguration(formEngineConfiguration);
  conf.addConfigurator(formEngineConfigurator);

  DmnEngineConfiguration dmnEngineConfiguration = new DmnEngineConfiguration();
  dmnEngineConfiguration.setDataSource(dataSource);

  DmnEngineConfigurator dmnEngineConfigurator = new DmnEngineConfigurator();
  dmnEngineConfigurator.setDmnEngineConfiguration(dmnEngineConfiguration);
  conf.addConfigurator(dmnEngineConfigurator);

  return conf;
}