會(huì)員版20就業(yè)課20雙元springdatajpa第二天講義

第1SpringDataJPASpringDataJPASpringDataJPA是Spring基于ORM框架、JPAJPA開(kāi)發(fā)者用極簡(jiǎn)的代碼即可實(shí)現(xiàn)對(duì)數(shù)據(jù)庫(kù)的和操作。它提供了包括增刪改查等在內(nèi)的常用功能，且易于擴(kuò)展！學(xué)習(xí)并使用SpringDataJPA可以極大提高開(kāi)發(fā)效率！SpringDataJPADAOCRUDSpringDataJPASpringDataJpa極大簡(jiǎn)化了數(shù)據(jù)庫(kù)層代碼。如何簡(jiǎn)化的呢？使用了SpringDataJpa，dao層中只需要寫接口，就自動(dòng)具有了增刪改查、分頁(yè)查詢等方法。SpringDataJPAJPAhibernateJPA是一套規(guī)范，內(nèi)部是有接口和抽象類組成的。hibernate是一套成ORM框架，而且API編程，意味著站在更高的角度上看待問(wèn)題（面向接口編程）SpringDataJPASpringJPAJPA規(guī)范下的專門第2SpringDataJPA的快速SpringDataJPACRUDSpringDataJPASpringDataJPASpringDataJPASpringSpringDataJPAJPA的服務(wù)hibernatespring相關(guān)坐標(biāo)，hibernate坐標(biāo)，數(shù)據(jù)庫(kù)驅(qū)動(dòng)坐標(biāo)等junit<!--springbeg--<!--springend--<!--hibernatebeg--<!--hibernateend--<!--c3p0beg--<!--c3p0end--<!--logend--<!--logend--elbeg使用springdatajpa<!--elend--SpringDataJPA<?xmlversion="1.0"encoding="UTF-<beans 1.dataSource配置數(shù)據(jù)庫(kù)連接池<beanid="dataSource" <propertyname="driverClass"value="com.mysql.jdbc.Driver"<propertyname="jdbcUrl"value="jdbc:mysql://localhost:3306/jpa"<propertyname="user"value="root"<propertyname="password"value="111111"2.配置entityManagerFactory<beanid="entityManagerFactory"<propertyname="dataSource"ref="dataSource"<propertyname="packagesToScan" .entity"<property<beanclass="org.hibernate.jpa.HibernatePersistenceProvider"<property<propertyname="generateDdl"value="false"<propertyname="database"value="MYSQL"<property <propertyname="showSql"value="true"<property<bean3.事務(wù)管理器JPA事務(wù)管理器<beanid="transactionManager"<propertyname="entityManagerFactory"ref="entityManagerFactory"整合springdatajpa<jpa:repositoriesbase- <!--4.txAdvice--<tx:adviceid="txAdvice"transaction-<tx:methodname="save*"<tx:methodname="insert*"<tx:methodname="update*"<tx:methodname="delete*"<tx:methodname="get*"read-<tx:methodname="find*"read-<tx:methodname="*"<!--5.aop--<aop:pointcutid="pointcut"expression="execution(* .service.*.*(..))"/><aop:advisoradvice-ref="txAdvice"pointcut-ref="pointcut"<<ponent-scanbase-packagepackageimportimportimportjavax.persistence.GeneratedValue;importjavax.persistence.GenerationType;importjavax.persistence.Id;import***@Entity ")//publicclassCustomer @GeneratedValue(strategy=GenerationType.IDENTITY配置主鍵的生成策略@Column(name="cust_id")//指定和表中cust_id字段的映射關(guān)系privateLong")//privateStringprivateStringprivateStringprivateStringprivateStringprivateStringpublicLonggetCustId()return}publicvoidsetCustId(LongcustId)this.custId=}publicStringgetCustName()return}publicvoidsetCustName(StringcustName)this.custName=}publicStringgetCustSource()return}publicvoidsetCustSource(StringcustSource)this.custSource=}publicStringgetCustIndustry()return}publicvoidsetCustIndustry(StringcustIndustry)this.custIndustry=}publicStringgetCustLevel()return}publicvoidsetCustLevel(StringcustLevel)this.custLevel=}publicStringgetCustAddress()return}publicvoidsetCustAddress(StringcustAddress)thisthis.custAddress=}publicStringgetCustPhone()return}publicvoidsetCustPhone(StringcustPhone)this.custPhone=}}SpringDataJPASpringDataJPADaopackagepackageimportimportimportimport }SpringDataJPADaoCRUDSpringDataJPASpringDataJPADao層接DaoCRUD操作publicclassCustomerDaoTestprivateCustomerDaopublicvoidtestSave(){CustomercnewCustomer(); }***publicvoidtestUpdate()Customercustomer= }publicvoidtestDelete(){}publicvoidtestFindById()Customercustomer=customerDao.findOne(2l);}}SpringDataJPASpringDataJPAJpaRepositoryJpaSpecificationExecutor接口，這樣就可以使用這些接口中定義的方法，但是這些方法都只是一些，沒(méi)有具體的實(shí)現(xiàn)方式，那么在SpringDataJPA中它又是怎么實(shí)現(xiàn)的呢？SpringDataJPAdebugSpringDataJPA 子類的實(shí)現(xiàn)過(guò)customerDao 生成的一個(gè)對(duì) 對(duì)象中方法調(diào)用的分JdkDynamicAopinvokecustomerDao對(duì)象生JdkDynamicAop生成的動(dòng)態(tài)對(duì)象當(dāng)中，而這個(gè)動(dòng)態(tài)對(duì)象就是通過(guò)SimpleJpaRepository的源碼分析，定位到了findOneSpringDataJPA完整的調(diào)用過(guò)程SpringDataJPA中接口定義JpaRepositoryJpaRepository接口后,我們就可以使用接口中定義的方法進(jìn)行查SpringDataJPA提供的查詢方法已經(jīng)可以解決大部分的應(yīng)用場(chǎng)景，但是對(duì)于某些業(yè)務(wù)來(lái)publicpublicinterfaceCustomerDaoextendsJpaRepository<Customer,Long>,JpaSpecificationExecutor<Customer>{@Query(value="frompublicList<Customer>@Query(value="fromCustomerwherecustName=publicCustomerfindCustomer(String}此外，也可以通過(guò)使用@Query來(lái)執(zhí)行一個(gè)更新操作，為此，我們需要在使用@Query的同時(shí)，用@Modifying來(lái)將該操作標(biāo)識(shí)為修改查詢，這樣框架最終會(huì)生成一個(gè)更新的操作，而非查詢@Query(value="update@Query(value="updateCustomersetcustName=?1wherecustId=?2")publicvoidupdateCustomer(StringcustName,LongSQLSpringDataJPAsql*nativeQuery使用本地sql@Query(value="select*frompublicvoid顧名思義，方法命名規(guī)則查詢就是根據(jù)方法的名字，就能創(chuàng)建查詢。只需要按照SpringJPA提供的方法命名規(guī)則定義方法的名稱，就可以完成查詢工作。SpringDataJPA在程序執(zhí)行SpringDataJPAfindBy開(kāi)頭，涉及條件查詢時(shí)，條件的屬性publicCustomerfindByCustName(String…wherex.lastname=andx.firstname=…wherex.lastname=?1x.firstname=…wherex.firstname=…wherebetween?1and…wherex.age<…wherex.age?…wherex.age>…wherex.age>=…wherex.startDate>…wherex.startDate<…wherex.ageis…wherex.agenot…wherex.firstnamelikelike…wherex.firstnamelike?1(parameterb