Mybatis+oracle adding a piece of data and returning the primary key problem for the added data

recently done Mybatis+oracle project to solve add a piece of data and return the primary key issue for the added data

Controller layer

@RequestMapping ("/addplan")    publicthrows  exception{         
//plan is the added data, Planid is the data primary key, when the primary key in the        object is null  int n = Service.insertonlineaddplan (plan);    
//Get Object primary key        System.out.println ("Return primary key value is" +Plan.getplanid ());                  return plan;    }

In the Mapperx.xml

 <insert id= "Insert" parametertype= "Com.online.pojo.OnlineAddplanWithBLOBs" > //gets the sequence value and assigns a value to the object's Planid field  <selectkey keyproperty= "Planid" resulttype= "DECIMAL" order= "before" > Select Online_sequence.nextval from dual  </selectkey> Insert into Online_addplan (PLANID, completetime, person, operation, USERNAME, Eventnode, workplan, Chengguo Miaoshu) 
 //gets the value of the Planid field in the above object  values (#{planid,jdbctype  =decimal}, # {Completetime,jdbctype=timestamp}, #{person,jdbctype=varchar}, #{operation, Jdbctype  =varchar}, #{username,jdbctype=varchar}, #{eventnode,jdbctype=CLOB} , #{workplan,jdbctype  =clob}, #{chengguomiaoshu,jdbctype=clob})  </ Insert> 

Mybatis+oracle adding a piece of data and returning the primary key problem for the added data