过程如下：

ParameterPage activityKeys = new ParameterPage();

ParameterPage activityParams = new ParameterPage();

activityKeys.putString("pxObjClass", "Rule-Obj-Activity");

activityKeys.putString("pyClassName", "CLASSNAME");

activityKeys.putString("pyActivityName", "ACTIVITYNAME");//调用具体类的名字和路径

activityParams.putString("PARAMNAME",ID); // 参数定义

tools.doActivity(activityKeys,tools.getStepPage(),activityParams);