Posts Tagged ‘源码研究’

[源码研究]jbpm中的异步Action

Posted on 2008/04/15, 3:16 pm, by zhangv, under 技术(Tech).

在jbpm中,如果action可以配置为异步执行
<action class=”ActionClassName” async=”true”></action>
如果是异步action,那么在flow执行到action所依附的节点时,会保存一个job,然后交由单独的job执行线程处理.源代
码:
GraphElement.java的executeActions方法:
if (action.isAsync()) {
ExecuteActionJob job = createAsyncActionExecutionJob(executionContext.getToken(), action);
MessageService messageService = (MessageService) Services.getCurrentService
(Services.SERVICENAME_MESSAGE);
messageService.send(job);
} else {
executeAction(action, executionContext);
}
这个job保存到数据库,并由JobExecutor去执行.
而jobExecutor在默认情况下是不会被启用的,需要手动启用或者配置为自动启动的servlet(JobExecutorServlet).
手动启动通过这个方法:
JbpmConfiguration.startJobExecutor()
还需要做的工作,在jbpm.cfg.xml里定义一个jobExecutor
<bean name=”jbpm.job.executor” class=”org.jbpm.job.executor.JobExecutor” singleton=”true” />
如果不用JbpmConfiguration应该也可以启动.做的事都是一样的,创建一个新的JobExecutor然后启动线程.只是猜测,没试过.
在3.1的数据库里是没有job的表的,升级到3.2.2后才有这个表.

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SpringIDE的误导

Posted on 2008/01/11, 3:10 pm, by zhangv, under 非技术(non-tech).

用springide验证了一下xml文件,得到这个错误
Destroy-method ’shutdown’ not found in bean class ‘org.enhydra.jdbc.pool.StandardXAPoolDataSource’
bean的配置如下:
也就是说springide认为这个bean没有shutdown的方法.查了一下xapool的source,发现是有的,但是是shutdown(boolean).destroy-method属性的定义:
Attribute : destroy-method
The name of the custom destroy method to invoke on bean factory shutdown. The method must
have no arguments, but may throw any exception. Note: Only invoked on beans whose lifecycle is
under the full control of the factory – which is always the case for singletons, [...]

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