Mybatis批量更新三种方式的实现

<update id= "updatebatch" parametertype= "java.util.list" >

   <foreach collection= "list" item= "item" index= "index" open= "" close= "" separator= ";" >

     update tablename

     <set>

       name=${item.name},

       name2=${item.name2}

     </set>

     where id = ${item.id}

   </foreach>  

</update>

<update id= "updatebatch" parametertype= "java.util.list" >

     update tablename

     <trim prefix= "set" suffixoverrides= "," >

       <trim prefix= "c_name =case" suffix= "end," >

         <foreach collection= "list" item= "cus" >

           < if test= "cus.name!=null" >

             when id=#{cus.id} then #{cus.name}

           </ if >

         </foreach>

       </trim>

       <trim prefix= "c_age =case" suffix= "end," >

         <foreach collection= "list" item= "cus" >

           < if test= "cus.age!=null" >

             when id=#{cus.id} then #{cus.age}

           </ if >

         </foreach>

       </trim>

     </trim>

     <where>

       <foreach collection= "list" separator= "or" item= "cus" >

         id = #{cus.id}

       </foreach>

     </where>

</update>

public int updatebatch(list<object> list){

     if (list == null || list.size() <= 0 ){

       return - 1 ;

     }

     sqlsessionfactory sqlsessionfactory = springcontextutil.getbean( "sqlsessionfactory" );

     sqlsession sqlsession = null ;

     try {

       sqlsession = sqlsessionfactory.opensession(executortype.batch, false );

       mapper mapper = sqlsession.getmapper(mapper. class );

       int batchcount = 1000 ; //提交数量,到达这个数量就提交

       for ( int index = 0 ; index < list.size(); index++) {

         object obj = list.get(index);

         mapper.updateinfo(obj);

         if (index != 0 && index%batchcount == 0 ){

           sqlsession.commit();

         }         

       }

       sqlsession.commit();

       return 0 ;

     } catch (exception e){

       sqlsession.rollback();

       return - 2 ;

     } finally {

       if (sqlsession != null ){

         sqlsession.close();

       }

     }

}

@component

public class springcontextutil implements applicationcontextaware{

   private static applicationcontext applicationcontext;

   @override

   public void setapplicationcontext(applicationcontext applicationcontext) throws beansexception {

     springcontextutil.applicationcontext = applicationcontext;

   }

   public static applicationcontext getapplicationcontext(){

     return applicationcontext;

   }

   public static object getbean( class t){

     try {

       return applicationcontext.getbean(t);

     } catch (beansexception e){

       return null ;

     }

   }

   public static object getbean(string name){

     try {

       return applicationcontext.getbean(name);

     } catch (beansexception e){

       return null ;

     }

   }

}