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>
View Code
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);
}
}
}
