方式,可將 useFastLane改 false,接著呼叫下列函式( Method),在約189列 private Page getCategories FromDAO(int start, int count, Locale locale throws Catalog Exception i ull dao= Catalog DAOFactory. getDAOO nt, locale) i catch( Catalog DAOSysException se)i throw new Catalog Exception(se. getMessageO) dao= CatalogDAoFactory, getDAOO這段程式的功用是透過 Catalog DAOFactory動態取得 Data Access Object, Data Access Object顧名思義它 是資料讀取的物件·這也是Java所建議的種 Design patternν通常我們會將連 接資料庫的JDBC相關設定’如 driver,url,及SQL語法包裝其中·集中控管 易於雜護。原始碼在 Petstore homelsrclcomponentslcataloglsrclcom\sun j2eelblueprintsIcatalog dao\Catal og DAOFactory java public static Catalog DAO getDAOO throws Catalog DAOSys Exception i Catalog DAO cat Dao= null InitialContext ic =new InitialContext( String class Name = String)ic lookup (UNDINames CATALOG DAO CLASS) cat Dao=( Catalog DAO) Class. forName(className). newInstanceO 3 catch(Naming Exception ne)( throw new Catalog DAOSys Exception ("Catalog DAOFactory.getDAO Naming Exception while getting DAO type: n"+ ne. getMessageO) i catch(Exception se)i throw new Catalog Exception("Catalog DAOFactory. getDAO Exception while getting DAO type: \n"+se. getMessageO) return cat dao.方式，可將 useFastLane 改為 false，接著呼叫下列函式(Method)，在約 189 列： private Page getCategoriesFromDAO(int start, int count, Locale locale) throws CatalogException { try { if (dao == null) dao = CatalogDAOFactory.getDAO(); return dao.getCategories(start, count, locale); } catch (CatalogDAOSysException se) { throw new CatalogException(se.getMessage()); } } dao = CatalogDAOFactory.getDAO() 這段程式的功用是透過 CatalogDAOFactory 動態取得 Data Access Object，Data Access Object 顧名思義它 是資料讀取的物件，這也是 Java 所建議的一種 Design Pattern，通常我們會將連 接資料庫的 JDBC 相關設定，如 driver,url，及 SQL 語法包裝其中，集中控管， 易於維護。原始碼在 Petstore_home\src\components\catalog\src\com\sun\j2ee\blueprints\catalog\dao\Catal ogDAOFactory.java public static CatalogDAO getDAO() throws CatalogDAOSysException { CatalogDAO catDao = null; try { InitialContext ic = new InitialContext(); String className = (String) ic.lookup (JNDINames.CATALOG_DAO_CLASS); catDao = (CatalogDAO) Class.forName(className).newInstance(); } catch (NamingException ne) { throw new CatalogDAOSysException("CatalogDAOFactory.getDAO: NamingException while getting DAO type : \n" + ne.getMessage()); } catch (Exception se) { throw new CatalogDAOSysException("CatalogDAOFactory.getDAO: Exception while getting DAO type : \n" + se.getMessage()); } return catDao; }