事务

public Map<String, Object> commitWork(JSONObject jsonObject){  Assignwork assign=new Assignwork();  assign.setTitle(jsonObject.getString("title"));  assign.set("startdate",getCurrentTime());  assign.set("enddate",jsonObject.getString("enddate"));  assign.setContent(jsonObject.getString("content"));  assign.setUserId(jsonObject.getString("userId"));  boolean flag =false;  flag= Db.tx(new IAtom() {    public boolean run(){     boolean res=assign.save();     if(res){String assginIdSql="select max(id) as id from cp_assignwork";int assignwork_id=Db.findFirst(assginIdSql).getInt("id");int count=0;     String sql="select * from cp_user_role where role_id='学生'";List<UserRole> students=UserRole.dao.find(sql);boolean res1=false;float score=-1;for(int i=0;i<students.size();i++){  Handwork handwork=new Handwork();  handwork.setAssignworkId(assignwork_id);  handwork.setUserId(students.get(i).getUserId()); //作业状态，0表示未完成，1表示已完成  handwork.setStatus("0");  handwork.setContent("");  handwork.setScore(score);  res1=handwork.save();  if(res1)    count++;  else    return false;}if(count==students.size()){  return true;}else{  return false;}    }else{return false;    }}});  Map<String, Object> result = new HashMap<String, Object>();  if (flag) {    result.put("flag", "1");  } else {   result.put("flag", "0");  }   return result;}