主講人：石云延遲符修改申請(qǐng)?jiān)O(shè)計(jì)Spring的數(shù)據(jù)庫(kù)開發(fā)與事務(wù)修改申請(qǐng)?jiān)O(shè)計(jì)

修改申請(qǐng)的主要功能是用戶在申請(qǐng)沒(méi)有審批之前，可以修改申請(qǐng)內(nèi)容。本任務(wù)實(shí)施的重點(diǎn)是事務(wù)的處理，即在修改時(shí)增加事務(wù)管理。本任務(wù)使用編程式事務(wù)管理，實(shí)現(xiàn)方式：使用TransactionManager實(shí)現(xiàn)編程事務(wù)；使用TransactionTemplate類實(shí)現(xiàn)編程事務(wù)。使用TransactionManager實(shí)現(xiàn)編程事務(wù)修改申請(qǐng)DAO實(shí)現(xiàn)類，增加DataSource、DataSourceTransactionManager、DefaultTransactionDefinition屬性的定義，在修改申請(qǐng)代碼中增加事務(wù)處理。修改申請(qǐng)的代碼如下所示。classApplyDAOimplementsIApplyDAO{ @Autowired privateJdbcTemplatejdbcTemplate; @Autowired privateDataSourcedataSource; @Autowired privateDataSourceTransactionManagertransactionManager; privateDefaultTransactionDefinitiondef;使用TransactionManager實(shí)現(xiàn)編程事務(wù)publicbooleanupdateApply(Applyapply){ //事務(wù)管理對(duì)象 transactionManager=newDataSourceTransactionManager(dataSource); //事務(wù)定義 def=newDefaultTransactionDefinition(); def.setPropagationBehavior(TransactionDefinition.PROPAGATION_REQUIRED); TransactionStatusstatus=transactionManager.getTransaction(def); inti=0; try{ finalintapplyId=apply.getApplyId(); finalStringtitle=apply.getTitle(); finalStringapplyContent=apply.getApplyContent(); finalStringapplyDate=apply.getApplyDate(); i=jdbcTemplate.update(newPreparedStatementCreator(){ publicPreparedStatementcreatePreparedStatement(Connectioncon) throwsSQLException{ Stringsql="updatetb_applicationsettitle=?,applyContent=?,applyDate=?whereapplyId=?"; PreparedStatementps=con.prepareStatement(sql); ps.setString(1,title); ……//設(shè)置applyContet、applyDate、applyId參數(shù) returnps;}});使用TransactionManager實(shí)現(xiàn)編程事務(wù)intj=jdbcTemplate.update(newPreparedStatementCreator(){ publicPreparedStatementcreatePreparedStatement(Connectioncon) throwsSQLException{ //故意設(shè)置update為updat Stringsql="updattb_applicationsettitle=?,applyContent=?,applyDate=?whereapplyId=?"; PreparedStatementps=con.prepareStatement(sql); ps.setString(1,title); ps.setString(1,title); ……//設(shè)置applyContet、applyDate、applyId參數(shù) returnps;}}); transactionMmit(status);//事務(wù)提交 }catch(DataAccessExceptione){ transactionManager.rollback(status);//事務(wù)回滾}……}使用TransactionTemplate類實(shí)現(xiàn)編程事務(wù)使用TransactionTemplate類實(shí)現(xiàn)編程事務(wù)首先創(chuàng)建TransactionTemplate對(duì)象，然后設(shè)置事務(wù)定義，調(diào)用execute()方法實(shí)現(xiàn)事務(wù)管理。修改的申請(qǐng)的代碼如下所示。//修改申請(qǐng):使用TransactionTemplate管理事務(wù)publicbooleanupdateApply(Applyapply){ finalintapplyId=apply.getApplyId(); finalStringtitle=apply.getTitle(); finalStringapplyContent=apply.getApplyContent(); finalStringapplyDate=apply.getApplyDate();transactionManager=newDataSourceTransactionManager(dataSource);//事務(wù)管理對(duì)象TransactionTemplatetransactionTemplate=newTransactionTemplate(transactionManager); transactionTemplate.setPropagationBehavior(TransactionDefinition.PROPAGATION_REQUIRED);

使用TransactionTemplate類實(shí)現(xiàn)編程事務(wù)transactionTemplate.execute(newTransactionCallbackWithoutResult(){protectedvoiddoInTransactionWithoutResult(TransactionStatusstatus){?jdbcTemplate.update(newPreparedStatementCreator(){?publicPreparedStatementcreatePreparedStatement(finalConnectioncon)throwsSQLException{?finalStringsql="updatetb_applicationsettitle=?,applyContent=?,applyDate=?whereapplyId=?";?finalPreparedStatementps=con.prepareStatement(sql);?ps.setString(1,title);?//ps設(shè)置applyContent、applyDate、applyId參數(shù)?returnps;}});??使用TransactionTemplate類實(shí)現(xiàn)編程事務(wù)intj=jdbcTemplate.update(newPreparedStatementCreator(){?publicPreparedStatementcreatePreparedStatement(Connectioncon)?throwsSQLException{?Stringsql="updattb_applicationsettitle=?,applyContent=?,applyDate=?whereapplyId=?";?PreparedStatementps=con.prepareStatement(sql);?