Program: 89923
Project: 89923
Buggy source:
public void processAnswer(VMOperationListener listener,long agentId,long seq,Answer answer){
  UserVmVO vm=listener.getVm();
  VMOperationParam param=listener.getParam();
  AsyncJobManager asyncMgr=getAsyncJobMgr();
  ManagementServer managementServer=asyncMgr.getExecutorContext().getManagementServer();
  String params="String_Node_Str" + vm.getId() + "String_Node_Str"+ vm.getHostName()+ "String_Node_Str"+ vm.getServiceOfferingId()+ "String_Node_Str"+ vm.getTemplateId()+ "String_Node_Str"+ vm.getDataCenterId();
  if (s_logger.isDebugEnabled())   s_logger.debug("String_Node_Str" + vm.getHostId() + "String_Node_Str"+ seq);
  boolean stopped=false;
  if (answer != null && answer.getResult())   stopped=true;
  boolean jobStatusUpdated=false;
  try {
    if (stopped) {
      asyncMgr.getExecutorContext().getVmMgr().completeStopCommand(param.getUserId(),vm,Event.OperationSucceeded,param.getEventId());
      asyncMgr.completeAsyncJob(getJob().getId(),AsyncJobResult.STATUS_SUCCEEDED,0,VMExecutorHelper.composeResultObject(asyncMgr.getExecutorContext().getManagementServer(),vm,null));
      jobStatusUpdated=true;
    }
 else {
      asyncMgr.getExecutorContext().getItMgr().stateTransitTo(vm,Event.OperationFailed,vm.getHostId());
      asyncMgr.completeAsyncJob(getJob().getId(),AsyncJobResult.STATUS_FAILED,BaseCmd.INTERNAL_ERROR,"String_Node_Str");
      jobStatusUpdated=true;
      EventUtils.saveEvent(param.getUserId(),param.getAccountId(),EventVO.LEVEL_ERROR,EventTypes.EVENT_VM_STOP,"String_Node_Str" + vm.getHostName(),params,param.getEventId());
    }
  }
 catch (  Exception e) {
    s_logger.error("String_Node_Str" + e.getMessage(),e);
    if (!jobStatusUpdated) {
      if (stopped) {
        asyncMgr.completeAsyncJob(getJob().getId(),AsyncJobResult.STATUS_SUCCEEDED,0,VMExecutorHelper.composeResultObject(asyncMgr.getExecutorContext().getManagementServer(),vm,null));
      }
 else {
        asyncMgr.completeAsyncJob(getJob().getId(),AsyncJobResult.STATUS_FAILED,BaseCmd.INTERNAL_ERROR,"String_Node_Str");
        EventUtils.saveEvent(param.getUserId(),param.getAccountId(),EventVO.LEVEL_ERROR,EventTypes.EVENT_VM_STOP,"String_Node_Str" + vm.getHostName(),params,param.getEventId());
      }
    }
  }
 finally {
    asyncMgr.releaseSyncSource(this);
  }
}

Fixed version (ground truth):
public void processAnswer(VMOperationListener listener,long agentId,long seq,Answer answer){
  UserVmVO vm=listener.getVm();
  VMOperationParam param=listener.getParam();
  AsyncJobManager asyncMgr=getAsyncJobMgr();
  ManagementServer managementServer=asyncMgr.getExecutorContext().getManagementServer();
  String params="String_Node_Str" + vm.getId() + "String_Node_Str"+ vm.getName()+ "String_Node_Str"+ vm.getServiceOfferingId()+ "String_Node_Str"+ vm.getTemplateId()+ "String_Node_Str"+ vm.getDataCenterId();
  if (s_logger.isDebugEnabled())   s_logger.debug("String_Node_Str" + vm.getHostId() + "String_Node_Str"+ seq);
  boolean stopped=false;
  if (answer != null && answer.getResult())   stopped=true;
  boolean jobStatusUpdated=false;
  try {
    if (stopped) {
      asyncMgr.getExecutorContext().getVmMgr().completeStopCommand(param.getUserId(),vm,Event.OperationSucceeded,param.getEventId());
      asyncMgr.completeAsyncJob(getJob().getId(),AsyncJobResult.STATUS_SUCCEEDED,0,VMExecutorHelper.composeResultObject(asyncMgr.getExecutorContext().getManagementServer(),vm,null));
      jobStatusUpdated=true;
    }
 else {
      asyncMgr.getExecutorContext().getItMgr().stateTransitTo(vm,Event.OperationFailed,vm.getHostId());
      asyncMgr.completeAsyncJob(getJob().getId(),AsyncJobResult.STATUS_FAILED,BaseCmd.INTERNAL_ERROR,"String_Node_Str");
      jobStatusUpdated=true;
      EventUtils.saveEvent(param.getUserId(),param.getAccountId(),EventVO.LEVEL_ERROR,EventTypes.EVENT_VM_STOP,"String_Node_Str" + vm.getName(),params,param.getEventId());
    }
  }
 catch (  Exception e) {
    s_logger.error("String_Node_Str" + e.getMessage(),e);
    if (!jobStatusUpdated) {
      if (stopped) {
        asyncMgr.completeAsyncJob(getJob().getId(),AsyncJobResult.STATUS_SUCCEEDED,0,VMExecutorHelper.composeResultObject(asyncMgr.getExecutorContext().getManagementServer(),vm,null));
      }
 else {
        asyncMgr.completeAsyncJob(getJob().getId(),AsyncJobResult.STATUS_FAILED,BaseCmd.INTERNAL_ERROR,"String_Node_Str");
        EventUtils.saveEvent(param.getUserId(),param.getAccountId(),EventVO.LEVEL_ERROR,EventTypes.EVENT_VM_STOP,"String_Node_Str" + vm.getName(),params,param.getEventId());
      }
    }
  }
 finally {
    asyncMgr.releaseSyncSource(this);
  }
}