SpringbootData中实现JPA
Posted Albert飞
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springDataJpa使用
0、引入依赖jar
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <parent> <artifactId>test_code</artifactId> <groupId>city.albert</groupId> <version>1.0-SNAPSHOT</version> </parent> <modelVersion>4.0.0</modelVersion> <artifactId>jpa</artifactId> <packaging>war</packaging> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> </dependency> <!--jpa相关--> <dependency> <groupId>org.springframework.data</groupId> <artifactId>spring-data-jpa</artifactId> <version>2.1.9.RELEASE</version> </dependency> <!-- https://mvnrepository.com/artifact/javax.el/javax.el-api --> <dependency> <groupId>javax.el</groupId> <artifactId>javax.el-api</artifactId> <version>3.0.0</version> </dependency> <!-- https://mvnrepository.com/artifact/javax.el/el-api --> <dependency> <groupId>javax.el</groupId> <artifactId>el-api</artifactId> <version>2.2</version> </dependency> <!--spring--> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> <version>5.2.5.RELEASE</version> </dependency> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjweaver</artifactId> <version>1.9.5</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>5.2.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>5.1.12.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-orm</artifactId> <version>5.1.8.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>5.2.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>5.2.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>5.2.5.RELEASE</version> </dependency> <!--hibernate--> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-ehcache</artifactId> <version>5.3.10.Final</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-entitymanager</artifactId> <version>5.3.10.Final</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-envers</artifactId> <version>5.3.10.Final</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.47</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.1.21</version> </dependency> </dependencies> <build> <finalName>jpa</finalName> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.3</version> <configuration> <encoding>utf-8</encoding> <source>1.8</source> <target>1.8</target> <!--编译时候记录形参--> <compilerArgs> <arg>-parameters</arg> </compilerArgs> </configuration> </plugin> <plugin> <groupId>org.apache.tomcat.maven</groupId> <artifactId>tomcat7-maven-plugin</artifactId> <version>2.2</version> <configuration> <port>8080</port> <path>/</path> <uriEncoding>UTF-8</uriEncoding> <server>tomcat7</server> </configuration> </plugin> </plugins> </build> <repositories> <repository> <id>central</id> <name>aliyun maven</name> <url>http://maven.aliyun.com/nexus/content/groups/public/</url> <layout>default</layout> <!-- 是否开启发布版构件下载 --> <releases> <enabled>true</enabled> </releases> <!-- 是否开启快照版构件下载 --> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories> </project>
1、配置xml
<?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:tx="http://www.springframework.org/schema/tx" xmlns:jpa="http://www.springframework.org/schema/data/jpa" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd"> <context:component-scan base-package="city.albert"/> <!--引入配置文件--> <context:property-placeholder location="classpath*:jdbc.properties"/> <!--配置数据源--> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource"> <property name="driverClassName" value="${classDr}"/> <property name="url" value="${url}"/> <property name="username" value="${username}"/> <property name="password" value="${password}"/> </bean> <!--jpa配置--> <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"> <!--设置数据源--> <property name="dataSource" ref="dataSource"/> <!--扫苗包--> <property name="packagesToScan" value="city.albert.entity"/> <!--jpa实现类--> <property name="persistenceProvider" > <bean class="org.hibernate.jpa.HibernatePersistenceProvider"/> </property> <!--jpa方言配置 不同jpa类似于事务的实现是不同的，应与上面保持一致--> <property name="jpaDialect"> <bean class="org.springframework.orm.jpa.vendor.HibernateJpaDialect"/> </property> <!--配置具体实现的属性--> <property name="jpaVendorAdapter"> <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"> <!--具体映射--> <!--配置数据表是否自动创建 通过实体类与数据表之间的映射--> <property name="generateDdl" value="false"/> <!--指定数据库--> <property name="database" value="MYSQL"/> <!--指定数据库方言，用于拼接sql--> <property name="databasePlatform" value="org.hibernate.dialect.MySQLDialect"/> <!--日志是否打印sql--> <property name="showSql" value="true"/> </bean> </property> </bean> <!--配置jpa的事务管理--> <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager"> <property name="entityManagerFactory" ref="entityManagerFactory"/> </bean> <!--配置jpa扫描包--> <jpa:repositories base-package="city.albert.dao" entity-manager-factory-ref="entityManagerFactory" transaction-manager-ref="transactionManager"/> <!--声明事务--> <tx:annotation-driven/> </beans>
2、配置dao接口
package city.albert.dao; import city.albert.entity.ResumeEntity; import org.springframework.data.jpa.repository.JpaRepository; import org.springframework.data.jpa.repository.JpaSpecificationExecutor; import org.springframework.data.jpa.repository.Query; /** * @author niunafei * @function * @email niunafei0315@163.com * @date 2020/6/25 8:52 PM * <p> * JpaRepository 封装基本的curd操作 * <p> * JpaSpecificationExecutor 封装了分页，排序等复杂操作 * <p> * 查询方式 * 1、findById或者findOne等jpa定义的方式进行查询 * 2、引入jps语言查询例如：queryById * 3、使用原生语言进行sql查询，需要自己写sql ，例如：queryByLike * 4、在接口中自己写接口，通过jpa的编写规则进行写，例如：findByNameLikeAndAddressLike * 5、动态查询 * -----条件的不同sql不同 * -----Optional<T> findOne(@Nullable Specification<T> var1); //根据条件进行查询单个对象 * -----List<T> findAll(@Nullable Specification<T> var1); //根据条件进行查询所有 * -----Page<T> findAll(@Nullable Specification<T> var1, Pageable var2); //根据条件进行分页查询 * -----List<T> findAll(@Nullable Specification<T> var1, Sort var2); //根据条件进行查询，并且排序 * -----long count(@Nullable Specification<T> var1); //根据条件进行查询总个数 */ public interface ResumeDao extends JpaRepository<ResumeEntity, Long>, JpaSpecificationExecutor<ResumeEntity> { /** * 基于jpa上的查询 * * @param id * @return */ @Query("from ResumeEntity where id=?1") ResumeEntity queryById(Long id); /** * 使用原生sql 进行查询 * * @param name * @param address * @return */ @Query(value = "select * from tb_resume where name like ?1 AND address like ?2 ", nativeQuery = true) ResumeEntity queryByLike(String name, String address); /** * 按照规则名进行查询 * 按照name和addree模糊查询 * 开头findBy * 属性名首字母大写 +查询方式 * * @param name * @param address * @return */ ResumeEntity findByNameLikeAndAddressLike(String name, String address); }
4、配置实体类
package city.albert.entity; import javax.persistence.*; /** * 简历实体类 简历属性与字段映射关系 * * @author niunafei * @function * @email niunafei0315@163.com * @date 2020/6/25 8:09 PM * <p> * 1、Entity声明是一个实体类对象 * 2、Table声明数据表与实体的对应关系 * 2、@Id 指定主键 * 3、@GeneratedValue 指定主键策略 * GenerationType.TABLE：使用一个特定的数据库表格来保存主键。 * GenerationType.SEQUENCE：根据底层数据库的序列来生成主键，条件是数据库支持序列。 * GenerationType.IDENTITY：主键由数据库自动生成（主要是自动增长型） * GenerationType.AUTO：主键由程序控制。 * 3、@Column 字段属性对应关系 */ @Entity @Table(name = "tb_resume") public class ResumeEntity { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) @Column(name = "id") private Long id; @Column(name = "name") private String name; @Column(name = "phone") private String phone; @Column(name = "address") private String address; public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getPhone() { return phone; } public void setPhone(String phone) { this.phone = phone; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } @Override public String toString() { return "ResumeEntity{" + "id=" + id + ", name=‘" + name + ‘‘‘ + ", phone=‘" + phone + ‘‘‘ + ", address=‘" + address + ‘‘‘ + ‘}‘; } }
5、测试
package city.albert; import city.albert.dao.ResumeDao; import city.albert.entity.ResumeEntity; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.domain.*; import org.springframework.data.jpa.domain.Specification; import org.springframework.lang.Nullable; import org.springframework.test.context.ContextConfiguration; import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import javax.persistence.criteria.*; import java.util.List; import java.util.Optional; /** * @author niunafei * @function * @email niunafei0315@163.com * @date 2020/6/25 9:10 PM */ @RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration(locations = {"classpath:applicationContext.xml"}) public class JpaTest { @Autowired private ResumeDao dao; /** * 查询 * 1、findById或者findOne等jpa定义的方式进行查询 * 2、引入jps语言查询例如：queryById * 3、使用原生语言进行sql查询，需要自己写sql ，例如：queryByLike * 4、在接口中自己写接口，通过jpa的编写规则进行写，例如：findByNameLikeAndAddressLike * 5、动态查询 * -----条件的不同sql不同 */ @Test public void test() { findById(); findOne(); saveOrUpdate(); findAll(); //查询jpa语法 ResumeEntity entity = dao.queryById(2L); System.out.println(entity); //原生sql，手动编写 ResumeEntity query = dao.queryByLike("%3%", "%3%"); System.out.println(query); //根据规则进行查询 ResumeEntity f = dao.findByNameLikeAndAddressLike("%3%", "%3%"); System.out.println(f); //实现动态sql拼接 Specification<ResumeEntity> specification = new Specification<ResumeEntity>() { @Nullable @Override public Predicate toPredicate(Root<ResumeEntity> root, CriteriaQuery<?> criteriaQuery, CriteriaBuilder criteriaBuilder) { //获取属性 Path<Object> name = root.get("name"); Path<Object> address = root.get("address"); //构建单个查询的条件 Predicate predicate = criteriaBuilder.equal(name, "李2"); //需要指定类型 Predicate like = criteriaBuilder.like(address.as(String.class), "%2%"); //整合查询条件 return criteriaBuilder.and(predicate, like); } }; Optional<ResumeEntity> one = dao.findOne(specification); System.out.println("动态拼接：" + one.get()); //排序与分页处理 Sort sort = new Sort(Sort.Direction.DESC, "id"); List<ResumeEntity> all = dao.findAll(sort); for (ResumeEntity d : all) { System.out.println("排序" + d); } //分页 Pageable pageable= PageRequest.of(1,2); Page<ResumeEntity> page = dao.findAll(pageable); for (ResumeEntity resumeEntity : page.getContent()) { System.out.println("分页：" + resumeEntity); } System.out.println(page.getTotalElements()+"-"+page.getNumber()+"-"+page.getSize()); } public void findById() { Optional<ResumeEntity> byId = dao.findById(1L); ResumeEntity resumeEntity = byId.get(); System.out.println(resumeEntity); } public void findOne() { ResumeEntity entity = new ResumeEntity(); entity.setId(1L); Example<ResumeEntity> of = Example.of(entity); Optional<ResumeEntity> byId = dao.findOne(of); ResumeEntity resumeEntity = byId.get(); System.out.println(resumeEntity); } public void saveOrUpdate() { ResumeEntity entity = new ResumeEntity(); entity.setAddress("测试测试"); entity.setName("测试测试"); entity.setPhone("12345678901"); ResumeEntity save = dao.save(entity); System.out.println(save.toString() + "----------------" + entity.toString()); save.setName("2342jhbhj"); ResumeEntity save1 = dao.save(save); System.out.println(save1.toString() + "----------------" + save.toString()); //删除 dao.deleteById(save1.getId()); } public void findAll() { List<ResumeEntity> all = dao.findAll(); for (ResumeEntity d : all) { System.out.println(d); } } }
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