一、配置数据库的连接属性
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package com.example.song.config;
import java.sql.SQLException;
import javax.sql.DataSource;
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 com.alibaba.druid.pool.DruidDataSource;
/**
* @ClassName: DruidDBConfig
* @Description: 设置数据库的连接属性
* @author songyunfei
* @date 2018年6月26日 下午3:51:53
*
*/
@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.url}")
private String dbUrl2;
@Value("${spring.datasource.secondary.username}")
private String username2;
@Value("${spring.datasource.secondary.password}")
private String password2;
@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") //设置注入bean的名称spring容器在注入通过byname 而不是bytype
@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;
}
}
二、主数据源（第一数据源）的配置
package com.example.song.config;
import java.util.Map;
import javax.annotation.Resource;
import javax.persistence.EntityManager;
import javax.sql.DataSource;
import org.springframework.beans.factory.annotation.Qualifier;
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="entityManagerFactoryPrimary",
transactionManagerRef="transactionManagerPrimary",
basePackages={"com.example.song.mapper.primary"})
public class PrimaryConfig {
@Resource
@Qualifier("primaryDataSource")
private DataSource primaryDataSource;
@Primary
@Bean(name = "entityManagerPrimary")
public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
return entityManagerFactoryPrimary(builder).getObject().createEntityManager();
}
@Resource
private JpaProperties jpaProperties;
private Map<String, Object> getVendorProperties() {
return jpaProperties.getHibernateProperties(new HibernateSettings());
}
/**
* 设置实体类的位置
*/
@Primary
@Bean(name="entityManagerFactoryPrimary")
public LocalContainerEntityManagerFactoryBean entityManagerFactoryPrimary(EntityManagerFactoryBuilder builder){
return builder.dataSource(primaryDataSource)
.packages("com.example.song.domain.primary")
.persistenceUnit("primaryPersistenceUnit")
.properties(getVendorProperties())
.build();
}
@Primary
@Bean(name="transactionManagerPrimary")
public PlatformTransactionManager transactionManagerPrimary(EntityManagerFactoryBuilder builder){
return new JpaTransactionManager(entityManagerFactoryPrimary(builder).getObject());
}
}
三、第二数据源的配置
package com.example.song.config;
import java.util.Map;
import javax.annotation.Resource;
import javax.persistence.EntityManager;
import javax.sql.DataSource;
import org.springframework.beans.factory.annotation.Qualifier;
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;
/**
*
* @ClassName: SecondaryDataSource
* @Description: 第二数据源的配置
* @author songyunfei
* @date 2018年6月26日 下午4:13:11
*
*/
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories( entityManagerFactoryRef = "entityManagerFactorySecondary",
transactionManagerRef = "transactionManagerSecondary",
basePackages = {"com.example.song.mapper.scondary"})
public class SecondaryConfig {
@Resource
@Qualifier("secondaryDataSource")
private DataSource secondaryDataSource;
@Bean(name = "entityManagerSecondary")
public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
return entityManagerFactorySecondary(builder).getObject().createEntityManager();
}
@Resource
private JpaProperties jpaProperties;
private Map<String, Object> getVendorProperties() {
return jpaProperties.getHibernateProperties(new HibernateSettings());
}
/**
* 设置实体类的位置
*/
@Bean(name="entityManagerFactorySecondary")
public LocalContainerEntityManagerFactoryBean entityManagerFactorySecondary(EntityManagerFactoryBuilder builder){
return builder.dataSource(secondaryDataSource)
.packages("com.example.song.domain.secondary")
.persistenceUnit("secondaryPersistenceUnit")
.properties(getVendorProperties())
.build();
}
@Bean(name="transactionManagerSecondary")
public PlatformTransactionManager transactionManagerSecondary(EntityManagerFactoryBuilder builder){
return new JpaTransactionManager(entityManagerFactorySecondary(builder).getObject());
}
}
总结：以上代码也是从网上其他的网友哪里copy过来，自己改了点配置，非常感谢其他网友的贡献
程序现在正常运行，但是还是有问题现在不是很清楚
①如果一个service中调用了两个数据源，那么事物怎么控制,自己写的demo中发现不同的数据源，一个数据源出错，还是会回滚的
②在实际的环境中，多数据源的使用会有哪些问题，目前我们公司还没有使用到多数据源