书p163代码hhh

package store . dao ;
/／省略包导入代码
 public class CategoryDAO (
 public List < Category > findCategories ( String name , Pager pager ) throws 
 Exception {
 List < Category > list = new ArrayList <>();
 Connection con = null ;
 PreparedStatement ps = null ;
 ResultSet rs = null ;
 try {
 Class . forName ( DB . JDBC _ DRIVER );
 con = DriverManager . getConnection ( DB . JDBC _ URL , DB . JDBC _ USER ,
 ps = con . prepareStatement (" select count ( id ) as total from t _ category 
 ps . setString (1,"%"+ name +"%");
 rs = ps . executeQuery ();
 if ( rs . next ()){
 DB . JDBC _ PASSWORD );
 where name like ?");
 pager . setTotal ( rs . getInt (" total "));
(
 ps = con . prepareStatement (" select * from t _ category where name 
 like ? limit ?,?");
 ps . setString (1,"%"+ name +"%");
 ps . setInt (2,( pager . getCurrentPage ()-1)* pager . getPageSize ());
 ps . setInt (3, pager . getPageSize ());
 rs = ps . executeQuery ();
 while ( rs . next ())(
 Category c = new Category ();
 c . setId ( rs . getInt (" id "));
 c . setName ( rs . getString (" name "));
 c . setDescription ( rs . getString (" description "));
 list . add ( c );
) catch ( Exception e ){
 e . printStackTrace ();
 throw new Exception ("数据库异常："+ e . getMessage ());