三、JPA和SpringData集成快速入门

   上节说到用JPA和Spring的集成使用到了DAO层的概念，在这里将会用repository来代替，你会发现以声明接口的方式去进行CRUD是多么的简便，废话少说开始代码实战吧，\(^o^)/~

一、万里长征始于 新建一个Web项目SpringData01，把相应的jar包放到/WebContent/WEB-INF/lib目录下

antlr-2.7.7.jar
c3p0-0.9.2.1.jar
com.springsource.net.sf.cglib-2.2.0.jar
com.springsource.org.aopalliance-1.0.0.jar
com.springsource.org.aspectj.weaver-1.6.8.RELEASE.jar
commons-logging-1.1.3.jar
dom4j-1.6.1.jar
hibernate-c3p0-4.2.4.Final.jar
hibernate-commons-annotations-4.0.2.Final.jar
hibernate-core-4.2.4.Final.jar
hibernate-entitymanager-4.2.4.Final.jar
hibernate-jpa-2.0-api-1.0.1.Final.jar
javassist-3.15.0-GA.jar
jboss-logging-3.1.0.GA.jar
jboss-transaction-api_1.1_spec-1.0.1.Final.jar
mchange-commons-java-0.2.3.4.jar
mysql-connector-java-5.1.7-bin.jar
slf4j-api-1.6.1.jar
spring-aop-4.0.0.RELEASE.jar
spring-aspects-4.0.0.RELEASE.jar
spring-beans-4.0.0.RELEASE.jar
spring-context-4.0.0.RELEASE.jar
spring-core-4.0.0.RELEASE.jar
spring-data-commons-1.6.2.RELEASE.jar
spring-data-jpa-1.4.2.RELEASE.jar
spring-expression-4.0.0.RELEASE.jar
spring-jdbc-4.0.0.RELEASE.jar
spring-orm-4.0.0.RELEASE.jar
spring-tx-4.0.0.RELEASE.jar
spring-web-4.0.0.RELEASE.jar
spring-webmvc-4.0.0.RELEASE.jar

二、配置web.xml不可以忘记哈

        

<?xml version="1.0" encoding="UTF-8"?><web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">  <display-name>SpirngData01</display-name>    <!-- needed for ContextLoaderListener --><context-param><param-name>contextConfigLocation</param-name><param-value>classpath:application.xml</param-value></context-param><!-- Bootstraps the root web application context before servlet initialization --><listener><listener-class>org.springframework.web.context.ContextLoaderListener</listener-class></listener></web-app>

三、配置application.xml实乃重中之重

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:context="http://www.springframework.org/schema/context"xmlns:jpa="http://www.springframework.org/schema/data/jpa"xmlns:tx="http://www.springframework.org/schema/tx"xmlns:repository="http://www.springframework.org/schema/data/repository"xsi:schemaLocation="http://www.springframework.org/schema/data/repository http://www.springframework.org/schema/data/repository/spring-repository-1.6.xsdhttp://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsdhttp://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsdhttp://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">   <!--配置扫描包  -->   <context:component-scan base-package="com.tan.springdata"/>   <!--加载本地properties文件 -->   <context:property-placeholder location="classpath:db.properties"/>  <!--配置数据源  -->  <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">  <property name="user" value="${jdbc.user}"></property>  <property name="password" value="${jdbc.password}"></property>  <property name="driverClass" value="${jdbc.driverClass}"></property>  <property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>  <property name="minPoolSize" value="${jdbc.minPoolSize}"></property><property name="maxPoolSize" value="${jdbc.maxPoolSize}"></property>  </bean>    <!--配置实体管理工厂类（容器管理类）  -->  <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">  <!--数据源依赖于上面声明  -->    <property name="dataSource" ref="dataSource"></property>    <!--实体包扫描  -->   <property name="packagesToScan" value="com.tan.springdata.entities"></property>   <!--JPA提供商 -->  <property name="jpaVendorAdapter">  <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"></bean>  </property>   <!--配置JPA实现者Hibernate的一些基本属性 -->   <property name="jpaProperties">  <props>  <prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop><prop key="hibernate.hbm2ddl.auto">update</prop><prop key="hibernate.show_sql">true</prop><prop key="hibernate.format_sql">true</prop><!-- *配置自动生成数据表列名的策略. 例如: lastName - last_name --><prop key="hibernate.ejb.naming_strategy">org.hibernate.cfg.ImprovedNamingStrategy</prop>  </props>     </property>  </bean>  <!-- 定义 Spring JPA 事务管理程序 -->  <bean id="jpaTransactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">  <property name="entityManagerFactory" ref="entityManagerFactory"/>  </bean>    <!-- 配置我们自己的repository并添加依赖 -->  <jpa:repositories base-package="com.tan.springdata.repositories"  entity-manager-factory-ref="entityManagerFactory"  transaction-manager-ref="jpaTransactionManager"/>    <!--声明注解驱动  -->  <tx:annotation-driven transaction-manager="jpaTransactionManager"/> </beans>

四、上面用到了db.properties

jdbc.user=rootjdbc.password=123456jdbc.driverClass=com.mysql.jdbc.Driverjdbc.jdbcUrl=jdbc:mysql:///jpa2jdbc.minPoolSize=5jdbc.maxPoolSize=10

五、还是得整Entity,不然没法继续，我将毫无保留全部粘出hh~

  Person.java

package com.tan.springdata.entities;import java.util.Date;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.GenerationType;import javax.persistence.Id;import javax.persistence.JoinColumn;import javax.persistence.ManyToOne;import javax.persistence.Table;import javax.persistence.Temporal;import javax.persistence.TemporalType;@Table(name="JPA_PERSONS")@Entitypublic class Person {private Integer id;private String lastName;private String email;private Date birth;private Address address;@GeneratedValue(strategy=GenerationType.AUTO)@Idpublic Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getLastName() {return lastName;}public void setLastName(String lastName) {this.lastName = lastName;}public String getEmail() {return email;}public void setEmail(String email) {this.email = email;}@Temporal(TemporalType.DATE)public Date getBirth() {return birth;}public void setBirth(Date birth) {this.birth = birth;}@Overridepublic String toString() {return "Person [id=" + id + ", lastName=" + lastName+"]";}@JoinColumn(name="ADDRESS_ID")@ManyToOnepublic Address getAddress() {return address;}public void setAddress(Address address) {this.address = address;}private String addressCity;public String getAddressCity() {return addressCity;}public void setAddressCity(String addressCity) {this.addressCity = addressCity;}}

Address.java

package com.tan.springdata.entities;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.GenerationType;import javax.persistence.Id;import javax.persistence.Table;@Table(name="JPA_ADDRESS")@Entitypublic class Address {private Integer id;private String city;private String province;@GeneratedValue(strategy=GenerationType.AUTO)@Idpublic Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getCity() {return city;}public void setCity(String city) {this.city = city;}public String getProvince() {return province;}public void setProvince(String province) {this.province = province;}}

六、是时候该建立自己的Repository了···

package com.tan.springdata.repositories;import java.util.List;import org.springframework.data.jpa.repository.JpaRepository;import org.springframework.data.jpa.repository.Modifying;import org.springframework.data.jpa.repository.Query;import org.springframework.data.repository.query.Param;import org.springframework.stereotype.Repository;import com.tan.springdata.entities.Person;@Repositorypublic interface PersonRepository extends JpaRepository<Person, Integer>{ //根据姓名获取Person对象Person getByLastName(String lastName);//根据给出的首字母匹配List<Person>getByLastNameStartingWith(String ln); //根据给出的任意字母匹配List<Person>getByLastNameLike(String ln);//addressCity//address -> cityList<Person> getByAddress_City(String city);//--------------------JPQL--------------------@Query("SELECT p FROM Person p WHERE p.birth = (SELECT min(p2.birth) FROM Person p2)")List<Person> getMaxAgePersons();//还需要使用 Service 包装一下, 添加事务//占位符的方式入参@Modifying@Query("UPDATE Person p SET p.lastName = ?1 WHERE p.id = ?2")void updatePersonLastName(String ln, int id);//起别名的方式入参@Modifying@Query("UPDATE Person p SET p.email = :e WHERE p.id = :id")void updatePersonEmail(@Param("id") Integer id, @Param("e") String email);    //使用本地SQL进行删除操作@Modifying@Query(value="DELETE FROM jpa_persons WHERE last_name = ?1", nativeQuery=true)void deleteByLastNameWithNativeSQL(String lastName);}

七、处理相关业务还是得加Service,谁说我们这里没有什么业务，但是也要加，因为大师说这是“思想”.

package com.tan.springdata.services;import java.util.List;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import org.springframework.transaction.annotation.Transactional;import com.tan.springdata.entities.Person;import com.tan.springdata.repositories.PersonRepository;@Service@Transactionalpublic class PersonService {@Autowiredprivate PersonRepository personRepository;public void saveOrUpdate(Person person){personRepository.save(person);}public Person getByLastName(String lastName){return personRepository.getByLastName(lastName);} public List<Person>getByLastNameStartingWith(String ln){ return personRepository.getByLastNameStartingWith(ln); }  public List<Person>getByLastNameLike(String ln){return personRepository.getByLastNameLike(ln); }  public List<Person>getAddressCity(String city){ return personRepository.getByAddress_City(city); }//--------------------JPQL-------------------- //查询年龄最大的人的集合 public List<Person>getMaxAgePersons(){ return personRepository.getMaxAgePersons(); }  //根据id更新lastName public void updateLastName(String lastName, Integer id){personRepository.updatePersonLastName(lastName, id);}//根据id更新Email public void updateEmail(String email, Integer id){personRepository.updatePersonEmail(id, email);}//根据用户名删除该对象 public void delete(String lastName){personRepository.deleteByLastNameWithNativeSQL(lastName);}}

八、好了，开始Testing....

package com.tan.springdata.test;import java.util.List;import org.junit.Test;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import com.tan.springdata.entities.Address;import com.tan.springdata.entities.Person;import com.tan.springdata.repositories.PersonRepository;import com.tan.springdata.services.PersonService;public class SpringDataTesting {private ApplicationContext ctx=null;private PersonService personService;private PersonRepository personRepository=null;{ctx=new ClassPathXmlApplicationContext("application.xml");personService=ctx.getBean(PersonService.class);personRepository=ctx.getBean(PersonRepository.class);}@Testpublic void testQueryBylastName() {Person person = personService.getByLastName("tan");System.out.println(person);String addressCity = person.getAddressCity();System.out.println(addressCity);}@Testpublic void getByLastNameStartingWith() {List<Person> person = personService.getByLastNameStartingWith("t");for(Person p:person){System.out.println(p);}}@Testpublic void getByLastNameLike() {List<Person> person = personService.getByLastNameLike("%a%");for(Person p:person){System.out.println(p);}}@Testpublic void getAddressCity() {List<Person> person = personService.getAddressCity("上海");for(Person p:person){System.out.println(p);}}   //------------------JPQL测试--------------------------------------@Testpublic void getMaxAgePersons() {List<Person> maxAgePersons = personService.getMaxAgePersons();for(Person p:maxAgePersons){System.out.println(p);}}@Testpublic void updateLastName() {personService.updateLastName("tanzhengqaing", 1);}@Testpublic void updateLastNddame() {personService.updateEmail("[e-mail]", 1);}    //经测试如果有多个同名的记录也一并删除@Testpublic void delete() {personService.delete("tan");}}

    本人测试，全部通过，如有不足之处烦请大牛指正！最后，学习贵在分享，请大家多提宝贵意见O(∩_∩)O~