Spring整合Hibernate实现Spring Data JPA （介绍和使用）

Spring Data JPA是Spring基于Hibernate开发的一个JPA框架。如果用过Hibernate或者MyBatis的话，就会知道对象关系映射（ORM）框架有多么方便。

但是Spring Data JPA框架功能更进一步，为我们做了一个数据持久层框架几乎能做的任何事情。下面来逐步介绍它的强大功能。

直接上代码：

pom.xml

        <!-- hibernate start -->
        <!-- spring data jpa  -->
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-jpa</artifactId>
            <version>2.1.3.RELEASE</version>
        </dependency>
        <!-- hibernate  -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>5.4.0.Final</version>
        </dependency>
        <!-- hibernate end  -->

项目结构：

the_data_jpa 包里面的各类代码

User

package com.oukele.the_data_jpa.entity;
 
import org.springframework.stereotype.Component;
 
import javax.persistence.*;
 
@Entity
@Table(name = "user")
public class User {
 
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "Id")
    private int id;
 
    @Column(name = "userName")
    private String name;
    private String password;
 
    public int getId() {
        return id;
    }
 
    public void setId(int id) {
        this.id = id;
    }
 
    public String getName() {
        return name;
    }
 
    public void setName(String name) {
        this.name = name;
    }
 
    public String getPassword() {
        return password;
    }
 
    public void setPassword(String password) {
        this.password = password;
    }
}

UserDao

package com.oukele.the_data_jpa.dao;
 
import com.oukele.the_data_jpa.entity.User;
import org.springframework.data.jpa.repository.JpaRepository;
 
import java.util.List;
 
public interface UserDao extends JpaRepository<User, Integer> {
 
    User findByNameAndPassword(String name,String password);
 
}

UserService

package com.oukele.the_data_jpa.service;
 
import com.oukele.the_data_jpa.dao.UserDao;
import com.oukele.the_data_jpa.entity.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.jpa.repository.Query;
import org.springframework.stereotype.Service;
 
import java.util.List;
 
@Service
public class UserService {
    @Autowired
    private UserDao userDao;
 
    public User findNameAndPassword(String name,String password){
        return userDao.findByNameAndPassword(name, password);
    }
 
    public List<User> list(){
        List<User> list = userDao.findAll();
        return list;
    }
}

SpringConfig

package com.oukele.the_data_jpa;
 
import com.mchange.v2.c3p0.ComboPooledDataSource;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.env.Environment;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
 
import javax.sql.DataSource;
import java.beans.PropertyVetoException;
import java.util.Properties;
 
@Configuration//声明当前配置类
@ComponentScan(basePackages = "com.oukele.the_data_jpa")// 扫描当前包 使用 spring 注解
@PropertySource("classpath:jdbc.properties")//加载 资源文件
@EnableJpaRepositories(basePackages = "com.oukele.the_data_jpa.dao")//扫描 使用 jpa 注解的接口
public class SpringConfig {
 
    //配置数据源
    @Bean
    DataSource dataSource(Environment env) throws PropertyVetoException {
        ComboPooledDataSource dataSource = new ComboPooledDataSource();
        dataSource.setDriverClass(env.getProperty("jdbc.driver"));
        dataSource.setJdbcUrl(env.getProperty("jdbc.url"));
        dataSource.setUser(env.getProperty("jdbc.user"));
        dataSource.setPassword(env.getProperty("jdbc.password"));
        return  dataSource;
    }
 
//    @Bean
//    public JdbcTemplate jdbcTemplate() {
//        JdbcTemplate jdbcTemplate = new JdbcTemplate();
//        jdbcTemplate.setDataSource(dataSource1);
//        return jdbcTemplate;
//    }
 
    @Bean
    public PlatformTransactionManager transactionManager(DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }
 
    //SqlSessionFactory
    @Bean
    LocalContainerEntityManagerFactoryBean entityManagerFactory(DataSource dataSource){
 
        LocalContainerEntityManagerFactoryBean bean = new LocalContainerEntityManagerFactoryBean();
        bean.setDataSource(dataSource);
        //加载 实体类
        bean.setPackagesToScan("com.oukele.the_data_jpa.entity");
        //设置 适配器
        bean.setJpaVendorAdapter(new HibernateJpaVendorAdapter());
 
        Properties properties = new Properties();
        //更新表结构
        properties.setProperty("hibernate.hbm2ddl.auto", "update");
        //设置方言
        properties.setProperty("hibernate.dialect", "org.hibernate.dialect.MySQLDialect");
        bean.setJpaProperties(properties);
 
        return bean;
    }
 
}

Main ( 测试类)

package com.oukele.the_data_jpa;

import com.oukele.the_data_jpa.entity.User;

import com.oukele.the_data_jpa.service.UserService;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

import java.util.List;

public class Main {

public static void main(String[] args) {

AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(SpringConfig.class);

UserService service = context.getBean(UserService.class);

User user = service.findNameAndPassword("oukele","oukele");

System.out.println(user.getName());

List<User> list = service.list();

for (User user1 : list) {

System.out.println(user1.getName()+" - "+user1.getPassword());

}

测试结果：

1 oukele
2 oukele - oukele

jdbc.properties文件：

jdbc.driver=org.mariadb.jdbc.Driver
jdbc.url=jdbc:mariadb://localhost:3306/test
jdbc.user=oukele
jdbc.password=oukele