随着Springboot升级到2.0,原来1.5.x的Jpa多数据源配置不能用了。现在总结一下Springboot2.0的jpa多数据源配置

连接池还是用druid,但是不能用druid的starter了,譬如在1.5.x时用的是

 

<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.6</version>
</dependency>

升级到2.0后,再用这个就会报错,因为一个AutoConfig的类缺失。那么要使用druid需要用下面的配置

<!--druid begin-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.10</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<!--druid end-->

 

注意log4j是druid强依赖的不能少,web是因为druid有web界面可以访问,也不能少。

 

 

application.yml也有变化

原来是这样的

 

spring:
jpa:
database: mysql
show-sql: true
hibernate:
ddl-auto: update
naming:
strategy: org.hibernate.cfg.ImprovedNamingStrategy #命名策略,加分隔线"_"

主要变化就是naming这里,原来的ImprovedNamingStrategy不让用了,改成了下面的类

spring:
datasource:
primary:
url: jdbc:mysql://localhost:3306/company?autoReconnect=true&useUnicode=true
username: root
password: root
secondary:
url: jdbc:mysql://localhost:3306/com1?autoReconnect=true&useUnicode=true
username: root
password: root
jpa:
database: mysql
generate-ddl: true
show-sql: true
hibernate:
ddl-auto: update
naming:
physical-strategy: org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy

 

 

 

双数据源:

 

 

先来配置druid的DataSource,这个类在新老版本里都能用,不需要变化。

package com.example.demo.druid;

import com.alibaba.druid.pool.DruidDataSource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.web.servlet.ServletComponentScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

import javax.sql.DataSource;
import java.sql.SQLException;

/**
* @author wuweifeng wrote on 2017/10/23.
* 数据库连接属性配置
*/
@ServletComponentScan
@Configuration
public class DruidDBConfig {
private Logger logger = LoggerFactory.getLogger(DruidDBConfig.class);

@Value("${spring.datasource.primary.url}")
private String dbUrl1;

@Value("${spring.datasource.primary.username}")
private String username1;

@Value("${spring.datasource.primary.password}")
private String password1;

@Value("${spring.datasource.secondary.username}")
private String username2;

@Value("${spring.datasource.secondary.password}")
private String password2;

@Value("${spring.datasource.secondary.url}")
private String dbUrl2;

@Value("com.mysql.jdbc.Driver")
private String driverClassName;

@Value("5")
private int initialSize;

@Value("5")
private int minIdle;

@Value("20")
private int maxActive;

@Value("60000")
private int maxWait;

/**
* 配置间隔多久才进行一次检测,检测需要关闭的空闲连接,单位是毫秒
*/
@Value("60000")
private int timeBetweenEvictionRunsMillis;
/**
* 配置一个连接在池中最小生存的时间,单位是毫秒
*/
@Value("300000")
private int minEvictableIdleTimeMillis;

@Value("SELECT 1 FROM DUAL")
private String validationQuery;

@Value("true")
private boolean testWhileIdle;

@Value("false")
private boolean testOnBorrow;

@Value("false")
private boolean testOnReturn;

/**
* 打开PSCache,并且指定每个连接上PSCache的大小
*/
@Value("true")
private boolean poolPreparedStatements;

@Value("20")
private int maxPoolPreparedStatementPerConnectionSize;
/**
* 配置监控统计拦截的filters,去掉后监控界面sql无法统计,'wall'用于防火墙
*/
@Value("stat,wall,log4j")
private String filters;
/**
* 通过connectProperties属性来打开mergeSql功能;慢SQL记录
*/
@Value("druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500")
private String connectionProperties;

@Bean(name = "primaryDataSource")
@Qualifier("primaryDataSource")
public DataSource dataSource() {
return getDruidDataSource(username1, password1, dbUrl1);
}

@Bean(name = "secondaryDataSource")
@Qualifier("secondaryDataSource")
@Primary
public DataSource secondaryDataSource() {
return getDruidDataSource(username2, password2, dbUrl2);
}

private DruidDataSource getDruidDataSource(String username, String password, String url) {
DruidDataSource datasource = new DruidDataSource();

datasource.setUrl(url);
datasource.setUsername(username);
datasource.setPassword(password);
datasource.setDriverClassName(driverClassName);

//configuration
datasource.setInitialSize(initialSize);
datasource.setMinIdle(minIdle);
datasource.setMaxActive(maxActive);
datasource.setMaxWait(maxWait);
datasource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);
datasource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
datasource.setValidationQuery(validationQuery);
datasource.setTestWhileIdle(testWhileIdle);
datasource.setTestOnBorrow(testOnBorrow);
datasource.setTestOnReturn(testOnReturn);
datasource.setPoolPreparedStatements(poolPreparedStatements);
datasource.setMaxPoolPreparedStatementPerConnectionSize(maxPoolPreparedStatementPerConnectionSize);
try {
datasource.setFilters(filters);
} catch (SQLException e) {
logger.error("druid configuration initialization filter : {0}", e);
}
datasource.setConnectionProperties(connectionProperties);

return datasource;
}
}

第一数据源:

package com.maimeng.pingtai.maimengoperate.db;

import org.springframework.beans.factory.annotation.Qualifier;
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.annotation.Resource;
import javax.persistence.EntityManager;
import javax.sql.DataSource;
import java.util.Properties;

/**
* Created by Administrator on 2017/8/11.
* <p>
* 数据源一
*/
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
entityManagerFactoryRef = "entityManagerFactoryPrimary",
transactionManagerRef = "transactionManagerPrimary",
basePackages = {"com.maimeng.pingtai.maimengoperate.repository.one"})
public class OneConfig {

@Resource
@Qualifier("primaryDataSource")
private DataSource primaryDataSource;

@Primary
@Bean(name = "entityManagerPrimary")
public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
return entityManagerFactoryPrimary(builder).getObject().createEntityManager();
}

@Resource
private Properties jpaProperties;

/**
* 设置实体类所在位置
*/
@Primary
@Bean(name = "entityManagerFactoryPrimary")
public LocalContainerEntityManagerFactoryBean entityManagerFactoryPrimary(EntityManagerFactoryBuilder builder) {
LocalContainerEntityManagerFactoryBean entityManagerFactory = builder
.dataSource(primaryDataSource)
.packages("com.maimeng.pingtai.maimengoperate.entity.one")
.persistenceUnit("primaryPersistenceUnit")
.build();
entityManagerFactory.setJpaProperties(jpaProperties);
return entityManagerFactory;
}

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

}

 

第二数据源:

package com.maimeng.pingtai.maimengoperate.db;

import org.springframework.beans.factory.annotation.Qualifier;
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.annotation.Resource;
import javax.persistence.EntityManager;
import javax.sql.DataSource;
import java.util.Properties;

/**
* Created by Administrator on 2017/8/11.
* <p>
* 数据源一
*/
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
entityManagerFactoryRef = "entityManagerFactorySecondary",
transactionManagerRef = "transactionManagerSecondary",
basePackages = {"com.maimeng.pingtai.maimengoperate.repository.two"}) //设置Repository所在位置
public class TwoConfig {

@Resource
@Qualifier("secondaryDataSource")
private DataSource secondaryDataSource;

@Resource
private Properties jpaProperties;


@Bean(name = "entityManagerSecondary")
public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
return entityManagerFactorySecondary(builder).getObject().createEntityManager();
}

@Bean(name = "entityManagerFactorySecondary")
public LocalContainerEntityManagerFactoryBean entityManagerFactorySecondary(EntityManagerFactoryBuilder builder) {
LocalContainerEntityManagerFactoryBean entityManagerFactory
= builder
.dataSource(secondaryDataSource)
.packages("com.maimeng.pingtai.maimengoperate.entity.two")//设置实体类所在位置
.persistenceUnit("secondaryPersistenceUnit")//持久化单元创建一个默认即可,多个便要分别命名
.build();
entityManagerFactory.setJpaProperties(jpaProperties);
return entityManagerFactory;
}

@Bean(name = "transactionManagerSecondary")
public PlatformTransactionManager transactionManagerPrimary(EntityManagerFactoryBuilder builder) {
return new JpaTransactionManager(entityManagerFactorySecondary(builder).getObject());
}
}

注意把里面的model包名和Repository包名替换为你自己的即可。

 

这样我们就完成了Springboot 2.*的多数据源Jpa配置了。

还有一个地方需要提一下,Springboot2.0依赖了Hibernate5.2版本,1.5.x依赖的是Hibernate5.0.12版本,这两个版本在处理Id自增方面是不一样的。

在老版本里,我们定义了

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "id")
public Long getId() {
return id;
}

Id生成策略为Auto,那么默认会被转出Id自增。

 

在新版本里,Auto是不行的,不会自增,而且Hibernate会额外创建出来一个表来专门维护Id。可以自行尝试一下,会多出来一个表。

我们如果需要自增的Id,需要显式指定

 

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id")
public Long getId() {
return id;
}