介绍#
JPA(Java Persistence API)Java 持久化 API,是 Java 持久化的标准规范,Hibernate 是持久化规范的技术实现,而 Spring Data JPA 是在 Hibernate 基础上封装的一款框架。
第一次使用 Spring JPA 的时候,感觉这东西简直就是神器,几乎不需要写什么关于数据库访问的代码一个基本的 CURD 的功能就出来了。在这篇文章中,我们将介绍 Spring Boot 整合 JPA 使用多个数据源的方法。
开发环境:
- Spring Boot 2.0.5
- Spring Data JPA 2.0.5
- MySQL 5.6
- JDK 8
- IDEA 2018.3
- Windows 10
引入依赖#
首先我们要 Spring Boot 引入 spring-boot-starter-data-jpa
依赖。
Maven 配置:
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<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
Gradle 配置:
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compile group: ‘org.springframework.boot‘, name: ‘spring-boot-starter-data-jpa‘, version: ‘2.0.5.RELEASE‘
compile group: ‘org.springframework.boot‘, name: ‘spring-boot-starter-web‘, version: ‘2.0.5.RELEASE‘
compile group: ‘org.springframework.boot‘, name: ‘spring-boot-devtools‘, version: ‘2.0.5.RELEASE‘
compile group: ‘mysql‘, name: ‘mysql-connector-java‘, version: ‘6.0.6‘
配置数据源#
Spring Boot 提供了使用 application.properties 或 application.yml 文件配置项目属性的方法。我比较习惯使用 application.yml 文件,所以这里我只列出 application.yml 文件的写法。
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spring:
datasource:
product:
driver-class-name: com.mysql.jdbc.Driver
jdbc-url: jdbc:mysql://127.0.0.1:3306/product?useUnicode=true&characterEncoding=utf-8&serverTimezone=UTC&autoReconnect=true&useSSL=false&zeroDateTimeBehavior=convertToNull
username: root
password: test123$
customer:
driver-class-name: com.mysql.jdbc.Driver
jdbc-url: jdbc:mysql://127.0.0.1:3306/customer?useUnicode=true&characterEncoding=utf-8&serverTimezone=UTC&autoReconnect=true&useSSL=false&zeroDateTimeBehavior=convertToNull
username: root
password: test123$
jpa:
generate-ddl: true
配置好 application.yml 文件后分别在数据库创建 customer 和 product 数据库。
添加实体(Entity)类#
客户实体:
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package com.springboot.jpa.customer.models;
import javax.persistence.*;
@Entity
public class Customer {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer id;
@Column(unique = true, nullable = false)
private String email;
private String firstName;
private String lastName;
protected Customer() {
}
public Customer(String email, String firstName, String lastName) {
this.email = email;
this.firstName = firstName;
this.lastName = lastName;
}
@Override
public String toString() {
return String.format("Customer[id=%d, firstName=‘%s‘, lastName=‘%s‘,email=‘%s‘]", id, firstName, lastName, email);
}
public Integer getId() {
return id;
}
public String getEmail() {
return email;
}
public String getFirstName() {
return firstName;
}
public String getLastName() {
return lastName;
}
}
产品实体:
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package com.springboot.jpa.product.models;
import javax.persistence.*;
@Entity
public class Product {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
@Column(nullable = false)
private String code;
private String name;
private double price;
protected Product() {
}
public Product(String code, String name, double price) {
this.code = code;
this.name = name;
this.price = price;
}
@Override
public String toString() {
return String.format("Product[id=%d, code=‘%s‘, name=‘%s‘, price=‘%s‘]", id, code, name, price);
}
public int getId() {
return id;
}
public String getCode() {
return code;
}
public String getName() {
return name;
}
public double getPrice() {
return price;
}
}
添加数据仓库(Repository)类#
客户 Repository:
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package com.springboot.jpa.customer.repository;
import com.springboot.jpa.customer.models.Customer;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;
@Repository
public interface CustomerRepository extends JpaRepository<Customer, Integer> {
}
产品 Repository:
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package com.springboot.jpa.product.repository;
import com.springboot.jpa.product.models.Product;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;
@Repository
public interface ProductRepository extends JpaRepository<Product, Integer> {
}
添加配置(Config)类#
客户配置:
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package com.springboot.jpa.customer.config;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import javax.persistence.EntityManagerFactory;
import javax.sql.DataSource;
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(entityManagerFactoryRef = "customerEntityManagerFactory", transactionManagerRef = "customerTransactionManager", basePackages = {"com.springboot.jpa.customer.repository"})
public class CustomerConfig {
@Primary
@Bean(name = "customerDataSource")
@ConfigurationProperties(prefix = "spring.datasource.customer")
public DataSource customerDataSource() {
return DataSourceBuilder.create().build();
}
@Primary
@Bean(name = "customerEntityManagerFactory")
public LocalContainerEntityManagerFactoryBean entityManagerFactory(EntityManagerFactoryBuilder builder, @Qualifier("customerDataSource") DataSource dataSource) {
return builder.dataSource(dataSource).packages("com.springboot.jpa.customer.models").persistenceUnit("customer").build();
}
@Primary
@Bean(name = "customerTransactionManager")
public PlatformTransactionManager customerTransactionManager(@Qualifier("customerEntityManagerFactory") EntityManagerFactory customerEntityManagerFactory) {
return new JpaTransactionManager(customerEntityManagerFactory);
}
}
产品配置:
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package com.springboot.jpa.product.config;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
import org.springframework.context.annotation.Bean;
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.LocalContainerEntityManagerFactoryBean;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import javax.persistence.EntityManagerFactory;
import javax.sql.DataSource;
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(entityManagerFactoryRef = "productEntityManagerFactory", transactionManagerRef = "productTransactionManager", basePackages = {"com.springboot.jpa.product.repository"}
)
public class ProductConfig {
@Bean(name = "productDataSource")
@ConfigurationProperties(prefix = "spring.datasource.product")
public DataSource dataSource() {
return DataSourceBuilder.create().build();
}
@Bean(name = "productEntityManagerFactory")
public LocalContainerEntityManagerFactoryBean barEntityManagerFactory(EntityManagerFactoryBuilder builder, @Qualifier("productDataSource") DataSource dataSource) {
return builder.dataSource(dataSource).packages("com.springboot.jpa.product.models").persistenceUnit("product").build();
}
@Bean(name = "productTransactionManager")
public PlatformTransactionManager productTransactionManager(@Qualifier("productEntityManagerFactory") EntityManagerFactory productEntityManagerFactory) {
return new JpaTransactionManager(productEntityManagerFactory);
}
}
项目结构:
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src/main/java
- com.springboot.jpa
- product
- config
- models
- repository
- customer
- config
- models
- repository
添加测试类#
客户测试类 CustomerDataSourcesTests:
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package com.springboot.jpa;
import com.springboot.jpa.customer.repository.CustomerRepository;
import com.springboot.jpa.customer.models.Customer;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.transaction.annotation.Transactional;
import org.junit.Test;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
@RunWith(SpringRunner.class)
@SpringBootTest
public class CustomerDataSourcesTests {
@Autowired
private CustomerRepository customerRepository;
@Test
@Transactional("customerTransactionManager")
public void createCustomer() {
Customer customer = new Customer("[email protected]", "Charles", "Zhang");
customer = customerRepository.save(customer);
assertNotNull(customerRepository.findById(customer.getId()));
assertEquals(customerRepository.findById(customer.getId()).get().getEmail(), "[email protected]");
}
}
产品测试类 ProductDataSourcesTests:
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package com.springboot.jpa;
import com.springboot.jpa.product.models.Product;
import com.springboot.jpa.product.repository.ProductRepository;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.transaction.annotation.Transactional;
import org.junit.Test;
import static org.junit.Assert.assertNotNull;
@RunWith(SpringRunner.class)
@SpringBootTest
public class ProductDataSourcesTests {
@Autowired
private ProductRepository productRepository;
@Test
@Transactional("productTransactionManager")
public void createProduct() {
Product product = new Product("10000", "Book", 80.0);
product = productRepository.save(product);
assertNotNull(productRepository.findById(product.getId()));
}
}
测试#
分别运行两个测试类通过后,查询数据库。
客户表:
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mysql> SELECT * FROM customer;
+----+-------------------+-----------+----------+
| id | email | firstName | lastName |
+----+-------------------+-----------+----------+
| 1 | [email protected] | Charles | Zhang |
+----+-------------------+-----------+----------+
1 row in set
产品表:
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mysql> SELECT * FROM product;
+----+-------+------+-------+
| id | code | name | price |
+----+-------+------+-------+
| 1 | 10000 | Book | 80 |
+----+-------+------+-------+
1 row in set
原文地址:https://www.cnblogs.com/pzrj123/p/12594095.html
时间: 2024-10-09 21:01:09