Spring : JPA的单独使用

title: 如何单独使用spring data jpa

引用pom文件:

        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-jpa</artifactId>
            <version>2.1.5.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>5.3.5.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-c3p0</artifactId>
            <version>5.3.5.Final</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <dependency>
            <groupId>com.mchange</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.5.2</version>
        </dependency>

编写配置类:

package com.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;

import javax.persistence.EntityManagerFactory;
import java.util.Properties;

/**
 * @author Zhai
 * 2019/04/02 15:10
 */

@Configuration
@ComponentScan(basePackages = {"com"})
// 指定Repository所在的包
@EnableJpaRepositories(basePackages = {"com.domain"})
public class JpaConfig {

    // 名字必须是entityManagerFactory,或者把@bean中name属性设置为entityManagerFactory
    @Bean
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
        LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
        // 设置数据库(如果在hibernate中配置了连接池,则不需要设置)
//        em.setDataSource(dataSource());
        // 指定Entity所在的包
        em.setPackagesToScan("com.domain");
        JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        em.setJpaVendorAdapter(vendorAdapter);
        // 配置属性
        Properties properties = new Properties();
        properties.setProperty("hibernate.connection.driver_class", "com.mysql.jdbc.Driver");
        properties.setProperty("hibernate.connection.url", "jdbc:mysql://10.8.3.38:3306/test");
        properties.setProperty("hibernate.connection.username", "root");
        properties.setProperty("hibernate.connection.password", "root");
        properties.setProperty("hibernate.dialect", "org.hibernate.dialect.MySQL5Dialect");
        properties.setProperty("hibernate.connection.provider_class", "org.hibernate.connection.C3P0ConnectionProvider");
        properties.setProperty("hibernate.c3p0.min_size", "1");
        properties.setProperty("hibernate.c3p0.max_size", "10");
        properties.setProperty("hibernate.hbm2ddl.auto", "create");
        properties.setProperty("hibernate.show_sql", "true");
        properties.setProperty("format_sql", "true");
        em.setJpaProperties(properties);
        return em;
    }
    // 名字必须是transactionManager,或者把@bean中name属性设置为transactionManager
    @Bean
    public PlatformTransactionManager transactionManager(
            EntityManagerFactory emf) {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(emf);
        return transactionManager;
    }
}

测试代码:

package com;

import com.config.JpaConfig;
import com.domain.Student;
import com.domain.StudentRepository;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

import java.util.List;

/**
 * @author Zhai
 * 2019/04/02 14:27
 */

public class JpaTest {
    public static void main(String[] args) {
        ApplicationContext context = new AnnotationConfigApplicationContext(JpaConfig.class);
        // 获取repository
        StudentRepository studentRepository = context.getBean(StudentRepository.class);
        Student student1 = new Student();
        studentRepository.save(student1);

        List<Student> students = studentRepository.findAll();
        System.out.println(students);

    }
}