spring orm - what's the different between SqlMapClient and SqlMapSeesion in ibatis? -

when read ibatis-sqlmap-2.3.4,i find both implements sqlmapexecutor.

sqlmapclientimpl insert localsqlmapsession provide thread safe.

but in spring2.5.6, execute method of sqlmapclienttemplate use sqlmapclientimpl this:

  sqlmapsession session = this.sqlmapclient.opensession();   ...   return action.doinsqlmapclient(session); 

the opensession method return new sqlmapsessionimpl each time.

my questions are:

why sqlmapclienttemplate use sqlmapseesion instead of sqlmapclient ?

why localsqlmapsession of sqlmapclient unused in sqlmapclienttemplate ? use this:

 return action.doinsqlmapclient(this.sqlmapclient); 

what's different between sqlmapclient , sqlmapseesion ?

for first question, spring-orm explain in comment:

// need use sqlmapsession, need pass spring-managed // connection (potentially transactional) in. shouldn't necessary if // run against transactionawaredatasourceproxy underneath, unfortunately // still need make ibatis batch execution work properly: if ibatis // doesn't recognize existing transaction, automatically executes // batch every single statement... 

the answer difference between ibatis' sqlmapclient , sqlmapsession can found in interface sqlmapclient's comments:

/** * returns single threaded sqlmapsession implementation use * 1 user.  remember though, sqlmapclient thread safe sqlmapsession * implementation, can work directly it.  if session * explicitly using method <b>be sure close it!</b>  can close session using * sqlmapsession.close() method. * <p/> * * @return sqlmapsession instance. */ public sqlmapsession opensession();