springboot 集成hibernate 多数据源链接

因为第一次接触双数据源，所以记录学习一下

此处我链接mysql数据源、SQL Server数据源

pom.xml文件：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-log4j</artifactId>
    <version>1.3.8.RELEASE</version>
</dependency>

<dependency>
    <groupId>com.microsoft.sqlserver</groupId>
    <artifactId>mssql-jdbc</artifactId>
    <scope>runtime</scope>
</dependency>
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <scope>runtime</scope>
</dependency>
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>

  properties配置文件如下：

   #mysql部分：

spring.datasource.hikari.middledb.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.hikari.middledb.jdbc-url=jdbc:mysql://127.0.0.1:3306/test1?serverTimezone=CTT&useUnicode=true&characterEncoding=UTF-8
spring.datasource.hikari.middledb.username=你的用户名
spring.datasource.hikari.middledb.password=你的密码
#spring.datasource.hikari.middledb.password=123456
spring.jpa.properties.hibernate.middledb.ddl-auto=update
spring.jpa.properties.middledb.database-platform=org.hibernate.dialect.MySQL5Dialect

#SQL Server部分：spring.datasource.hikari.erpdb.driver-class-name=com.microsoft.sqlserver.jdbc.SQLServerDriver

spring.datasource.hikari.erpdb.jdbc-url=jdbc:sqlserver://127.0.0.1;SelectMethod=cursor;DatabaseName=test2
spring.datasource.hikari.erpdb.username=你的用户名
spring.datasource.hikari.erpdb.password=你的密码
spring.jpa.properties.hibernate.erpdb.ddl-auto=update
spring.jpa.properties.erpdb.database-platform=org.hibernate.dialect.SQLServer2012Dialect
#sql日志设置spring.jpa.show-sql=truespring.jpa.properties.hibernate.format_sql=true

logging.level.org.hibernate.type.descriptor.sql.BasicBinder=trace
spring.jackson.serialization.indent-output=true
spring.jpa.hibernate.naming.physical-strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl

#编码设置
spring.http.encoding.force=true
spring.http.encoding.charset=UTF-8
spring.http.encoding.enabled=true
server.tomcat.uri-encoding=UTF-8
server.port=8011

接着需要添加数据源的配置类：

DataSourceConfig.java

import javax.sql.DataSource;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

@Configuration
public class DataSourceConfig {
    
    @Bean(name = "middleDataSource") #配置到spring的容器中
    @Qualifier("middleDataSource")   #Qualifiler()的作用是准确绑定mysqlDataSource名字
    @Primary   #表示主数据源
    @ConfigurationProperties(prefix = "spring.datasource.hikari.middledb")
    public DataSource middleDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "erpserverDataSource")
    @Qualifier("erpserverDataSource")
    @ConfigurationProperties(prefix = "spring.datasource.hikari.erpdb")
    public DataSource erpDataSource() {
        return DataSourceBuilder.create().build();
    }
}

次数据源的配置类：即 ErpDataSourceConfig.java

import java.util.Map;
import java.util.Objects;

import javax.persistence.EntityManager;
import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateProperties;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateSettings;
import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
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;

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(entityManagerFactoryRef = "entityManagerFactoryErp", transactionManagerRef = "transactionManagerErp", basePackages = {"com.kwg.sap.dao.erp"})
public class ErpDatasourceConfig {

    private final DataSource erpDataSource;

    private final JpaProperties jpaProperties;

    private final HibernateProperties hibernateProperties;

    @Value("${spring.jpa.properties.erpdb.database-platform}")
    private String erpDialect;// 获取对应的数据库方言

    @Value("${spring.jpa.properties.hibernate.erpdb.ddl-auto}")
    private String erpDdlAuto;// 获取对应的数据库方言

    @Autowired
    public ErpDatasourceConfig(@Qualifier("erpDataSource") DataSource erpDataSource, JpaProperties jpaProperties, HibernateProperties hibernateProperties) {
        this.erpDataSource = erpDataSource;
        this.jpaProperties = jpaProperties;
        this.hibernateProperties = hibernateProperties;
    }

    @Bean(name = "entityManagerErp")
    public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
        return Objects.requireNonNull(entityManagerFactoryErp(builder).getObject()).createEntityManager();
    }

    @Bean(name = "entityManagerFactoryErp")
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryErp(EntityManagerFactoryBuilder builder) {
        return builder.dataSource(erpDataSource)
                .packages("com.kwg.sap.entity.erp").persistenceUnit("erpPersistenceUnit")
                .properties(getVendorProperties()).build();
    }

    private Map<String, Object> getVendorProperties() {
        jpaProperties.setDatabasePlatform(erpDialect);
//        jpaProperties.setShowSql(true);
        System.err.println("当前选用方言：" + jpaProperties.getDatabasePlatform());
        hibernateProperties.setDdlAuto(erpDdlAuto);
        return hibernateProperties.determineHibernateProperties(jpaProperties.getProperties(), new HibernateSettings());
    }

    @Bean(name = "transactionManagerErp")
    public PlatformTransactionManager transactionManagerErp(EntityManagerFactoryBuilder builder) {
        return new JpaTransactionManager(entityManagerFactoryErp(builder).getObject());
    }
}

主数据源的配置类：

import java.util.Map;
import java.util.Objects;

import javax.persistence.EntityManager;
import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateProperties;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateSettings;
import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
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;

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(entityManagerFactoryRef = "entityManagerFactoryMiddle", transactionManagerRef = "transactionManagerMiddle", basePackages = {
        "com.kwg.sap.dao.middle"})
public class MiddleDatasourceConfig {

    private final DataSource middleDataSource;

    private final JpaProperties jpaProperties;

    private final HibernateProperties hibernateProperties;

    @Value("${spring.jpa.properties.middledb.database-platform}")
    private String middleDialect;// 获取对应的数据库方言

    @Value("${spring.jpa.properties.hibernate.middledb.ddl-auto}")
    private String middleDdlAuto;// 获取对应的数据库方言

    @Autowired
    public MiddleDatasourceConfig(@Qualifier("middleDataSource") DataSource middleDataSource, JpaProperties jpaProperties, HibernateProperties hibernateProperties) {
        this.middleDataSource = middleDataSource;
        this.jpaProperties = jpaProperties;
        this.hibernateProperties = hibernateProperties;
    }

    @Primary
    @Bean(name = "entityManagerMiddle")
    public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
        return Objects.requireNonNull(entityManagerFactoryMiddle(builder).getObject()).createEntityManager();
    }

    @Primary
    @Bean(name = "entityManagerFactoryMiddle")
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryMiddle(EntityManagerFactoryBuilder builder) {
        return builder.dataSource(middleDataSource)
                .packages("com.kwg.sap.entity.middle").persistenceUnit("middlePersistenceUnit")
                .properties(getVendorProperties()).build();
    }

    private Map<String, Object> getVendorProperties() {
        jpaProperties.setDatabasePlatform(middleDialect);
//        jpaProperties.setShowSql(true);
        System.err.println("当前选用方言：" + jpaProperties.getDatabasePlatform());
        hibernateProperties.setDdlAuto(middleDdlAuto);
        return hibernateProperties.determineHibernateProperties(jpaProperties.getProperties(), new HibernateSettings());
    }

    @Primary
    @Bean(name = "transactionManagerMiddle")
    public PlatformTransactionManager transactionManagerMiddle(EntityManagerFactoryBuilder builder) {
        return new JpaTransactionManager(entityManagerFactoryMiddle(builder).getObject());
    }
}

双数据源配置到此为止：至于数据库的调用层：DAO层如下（假设 UserDAO）,怎么操作，都是像单数据源一样操作，这里之所以能映射到对应数据库的User表，是因为在数据源配置类的时候，已经扫描了User所在的包，即已经绑定了是mysql数据库还是sql Server数据库
@Repository 
public interface UserDAO extends JpaRepository<User, Long> {

}