如何配置和使用两个数据源?
例如,这是我的第一个数据源:
application.properties
#first db
spring.datasource.url = [url]
spring.datasource.username = [username]
spring.datasource.password = [password]
spring.datasource.driverClassName = oracle.jdbc.OracleDriver
#second db ...
应用程序类
@SpringBootApplication
public class SampleApplication
{
public static void main(String[] args) {
SpringApplication.run(SampleApplication.class, args);
}
}
如何修改应用。属性添加另一个数据源?我如何自动装配它以供不同的存储库使用?
我用的是mybatis springboot 2.0技术栈,
解决方案:
//application.properties - start
sp.ds1.jdbc-url=jdbc:mysql://localhost:3306/mydb?useSSL=false
sp.ds1.username=user
sp.ds1.password=pwd
sp.ds1.testWhileIdle=true
sp.ds1.validationQuery=SELECT 1
sp.ds1.driverClassName=com.mysql.jdbc.Driver
sp.ds2.jdbc-url=jdbc:mysql://localhost:4586/mydb?useSSL=false
sp.ds2.username=user
sp.ds2.password=pwd
sp.ds2.testWhileIdle=true
sp.ds2.validationQuery=SELECT 1
sp.ds2.driverClassName=com.mysql.jdbc.Driver
//application.properties - end
//configuration class
@Configuration
@ComponentScan(basePackages = "com.mypkg")
public class MultipleDBConfig {
public static final String SQL_SESSION_FACTORY_NAME_1 = "sqlSessionFactory1";
public static final String SQL_SESSION_FACTORY_NAME_2 = "sqlSessionFactory2";
public static final String MAPPERS_PACKAGE_NAME_1 = "com.mypg.mymapper1";
public static final String MAPPERS_PACKAGE_NAME_2 = "com.mypg.mymapper2";
@Bean(name = "mysqlDb1")
@Primary
@ConfigurationProperties(prefix = "sp.ds1")
public DataSource dataSource1() {
System.out.println("db1 datasource");
return DataSourceBuilder.create().build();
}
@Bean(name = "mysqlDb2")
@ConfigurationProperties(prefix = "sp.ds2")
public DataSource dataSource2() {
System.out.println("db2 datasource");
return DataSourceBuilder.create().build();
}
@Bean(name = SQL_SESSION_FACTORY_NAME_1)
@Primary
public SqlSessionFactory sqlSessionFactory1(@Qualifier("mysqlDb1") DataSource dataSource1) throws Exception {
System.out.println("sqlSessionFactory1");
SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
sqlSessionFactoryBean.setTypeHandlersPackage(MAPPERS_PACKAGE_NAME_1);
sqlSessionFactoryBean.setDataSource(dataSource1);
SqlSessionFactory sqlSessionFactory = sqlSessionFactoryBean.getObject();
sqlSessionFactory.getConfiguration().setMapUnderscoreToCamelCase(true);
sqlSessionFactory.getConfiguration().setJdbcTypeForNull(JdbcType.NULL);
return sqlSessionFactory;
}
@Bean(name = SQL_SESSION_FACTORY_NAME_2)
public SqlSessionFactory sqlSessionFactory2(@Qualifier("mysqlDb2") DataSource dataSource2) throws Exception {
System.out.println("sqlSessionFactory2");
SqlSessionFactoryBean diSqlSessionFactoryBean = new SqlSessionFactoryBean();
diSqlSessionFactoryBean.setTypeHandlersPackage(MAPPERS_PACKAGE_NAME_2);
diSqlSessionFactoryBean.setDataSource(dataSource2);
SqlSessionFactory sqlSessionFactory = diSqlSessionFactoryBean.getObject();
sqlSessionFactory.getConfiguration().setMapUnderscoreToCamelCase(true);
sqlSessionFactory.getConfiguration().setJdbcTypeForNull(JdbcType.NULL);
return sqlSessionFactory;
}
@Bean
@Primary
public MapperScannerConfigurer mapperScannerConfigurer1() {
System.out.println("mapperScannerConfigurer1");
MapperScannerConfigurer configurer = new MapperScannerConfigurer();
configurer.setBasePackage(MAPPERS_PACKAGE_NAME_1);
configurer.setSqlSessionFactoryBeanName(SQL_SESSION_FACTORY_NAME_1);
return configurer;
}
@Bean
public MapperScannerConfigurer mapperScannerConfigurer2() {
System.out.println("mapperScannerConfigurer2");
MapperScannerConfigurer configurer = new MapperScannerConfigurer();
configurer.setBasePackage(MAPPERS_PACKAGE_NAME_2);
configurer.setSqlSessionFactoryBeanName(SQL_SESSION_FACTORY_NAME_2);
return configurer;
}
}
注意:
1)@Primary -> @Primary
2)。属性中的“jdbc-url”-> Spring Boot 2.0迁移后:需要jdbcUrl和driverClassName
这里是完整的解决方案
#First Datasource (DB1)
db1.datasource.url: url
db1.datasource.username:user
db1.datasource.password:password
#Second Datasource (DB2)
db2.datasource.url:url
db2.datasource.username:user
db2.datasource.password:password
因为我们要访问两个不同的数据库(db1, db2),所以我们需要分别配置每个数据源配置,如下所示:
public class DB1_DataSource {
@Autowired
private Environment env;
@Bean
@Primary
public LocalContainerEntityManagerFactoryBean db1EntityManager() {
LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
em.setDataSource(db1Datasource());
em.setPersistenceUnitName("db1EntityManager");
HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
em.setJpaVendorAdapter(vendorAdapter);
HashMap<string, object=""> properties = new HashMap<>();
properties.put("hibernate.dialect",
env.getProperty("hibernate.dialect"));
properties.put("hibernate.show-sql",
env.getProperty("jdbc.show-sql"));
em.setJpaPropertyMap(properties);
return em;
}
@Primary
@Bean
public DataSource db1Datasource() {
DriverManagerDataSource dataSource
= new DriverManagerDataSource();
dataSource.setDriverClassName(
env.getProperty("jdbc.driver-class-name"));
dataSource.setUrl(env.getProperty("db1.datasource.url"));
dataSource.setUsername(env.getProperty("db1.datasource.username"));
dataSource.setPassword(env.getProperty("db1.datasource.password"));
return dataSource;
}
@Primary
@Bean
public PlatformTransactionManager db1TransactionManager() {
JpaTransactionManager transactionManager
= new JpaTransactionManager();
transactionManager.setEntityManagerFactory(
db1EntityManager().getObject());
return transactionManager;
}
}
第二数据源:
public class DB2_DataSource {
@Autowired
private Environment env;
@Bean
public LocalContainerEntityManagerFactoryBean db2EntityManager() {
LocalContainerEntityManagerFactoryBean em
= new LocalContainerEntityManagerFactoryBean();
em.setDataSource(db2Datasource());
em.setPersistenceUnitName("db2EntityManager");
HibernateJpaVendorAdapter vendorAdapter
= new HibernateJpaVendorAdapter();
em.setJpaVendorAdapter(vendorAdapter);
HashMap<string, object=""> properties = new HashMap<>();
properties.put("hibernate.dialect",
env.getProperty("hibernate.dialect"));
properties.put("hibernate.show-sql",
env.getProperty("jdbc.show-sql"));
em.setJpaPropertyMap(properties);
return em;
}
@Bean
public DataSource db2Datasource() {
DriverManagerDataSource dataSource
= new DriverManagerDataSource();
dataSource.setDriverClassName(
env.getProperty("jdbc.driver-class-name"));
dataSource.setUrl(env.getProperty("db2.datasource.url"));
dataSource.setUsername(env.getProperty("db2.datasource.username"));
dataSource.setPassword(env.getProperty("db2.datasource.password"));
return dataSource;
}
@Bean
public PlatformTransactionManager db2TransactionManager() {
JpaTransactionManager transactionManager
= new JpaTransactionManager();
transactionManager.setEntityManagerFactory(
db2EntityManager().getObject());
return transactionManager;
}
}
你可以在我的博客上找到完整的例子:
使用多个数据源配置的Spring引导
给你。
添加到您的应用程序中。属性文件:
#first db
spring.datasource.url = [url]
spring.datasource.username = [username]
spring.datasource.password = [password]
spring.datasource.driverClassName = oracle.jdbc.OracleDriver
#second db ...
spring.secondDatasource.url = [url]
spring.secondDatasource.username = [username]
spring.secondDatasource.password = [password]
spring.secondDatasource.driverClassName = oracle.jdbc.OracleDriver
在任何带@Configuration注解的类中添加以下方法:
@Bean
@Primary
@ConfigurationProperties(prefix="spring.datasource")
public DataSource primaryDataSource() {
return DataSourceBuilder.create().build();
}
@Bean
@ConfigurationProperties(prefix="spring.secondDatasource")
public DataSource secondaryDataSource() {
return DataSourceBuilder.create().build();
}
我还必须从Spring Boot应用程序中建立到2个数据源的连接,这并不容易——Spring Boot文档中提到的解决方案不起作用。经过长时间的网上挖掘,我让它工作,主要思想是从这篇文章和一堆其他地方。
下面的解决方案是用Kotlin编写的,适用于Spring Boot 2.1.3和Hibernate Core 5.3.7。主要问题是,仅仅设置不同的DataSource配置是不够的,还必须为两个数据库配置EntityManagerFactory和TransactionManager。
下面是第一个(主)数据库的配置:
@Configuration
@EnableJpaRepositories(
entityManagerFactoryRef = "firstDbEntityManagerFactory",
transactionManagerRef = "firstDbTransactionManager",
basePackages = ["org.path.to.firstDb.domain"]
)
@EnableTransactionManagement
class FirstDbConfig {
@Bean
@Primary
@ConfigurationProperties(prefix = "spring.datasource.firstDb")
fun firstDbDataSource(): DataSource {
return DataSourceBuilder.create().build()
}
@Primary
@Bean(name = ["firstDbEntityManagerFactory"])
fun firstDbEntityManagerFactory(
builder: EntityManagerFactoryBuilder,
@Qualifier("firstDbDataSource") dataSource: DataSource
): LocalContainerEntityManagerFactoryBean {
return builder
.dataSource(dataSource)
.packages(SomeEntity::class.java)
.persistenceUnit("firstDb")
// Following is the optional configuration for naming strategy
.properties(
singletonMap(
"hibernate.naming.physical-strategy",
"org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl"
)
)
.build()
}
@Primary
@Bean(name = ["firstDbTransactionManager"])
fun firstDbTransactionManager(
@Qualifier("firstDbEntityManagerFactory") firstDbEntityManagerFactory: EntityManagerFactory
): PlatformTransactionManager {
return JpaTransactionManager(firstDbEntityManagerFactory)
}
}
这是第二个数据库的配置:
@Configuration
@EnableJpaRepositories(
entityManagerFactoryRef = "secondDbEntityManagerFactory",
transactionManagerRef = "secondDbTransactionManager",
basePackages = ["org.path.to.secondDb.domain"]
)
@EnableTransactionManagement
class SecondDbConfig {
@Bean
@ConfigurationProperties("spring.datasource.secondDb")
fun secondDbDataSource(): DataSource {
return DataSourceBuilder.create().build()
}
@Bean(name = ["secondDbEntityManagerFactory"])
fun secondDbEntityManagerFactory(
builder: EntityManagerFactoryBuilder,
@Qualifier("secondDbDataSource") dataSource: DataSource
): LocalContainerEntityManagerFactoryBean {
return builder
.dataSource(dataSource)
.packages(EntityFromSecondDb::class.java)
.persistenceUnit("secondDb")
.build()
}
@Bean(name = ["secondDbTransactionManager"])
fun secondDbTransactionManager(
@Qualifier("secondDbEntityManagerFactory") secondDbEntityManagerFactory: EntityManagerFactory
): PlatformTransactionManager {
return JpaTransactionManager(secondDbEntityManagerFactory)
}
}
数据源的属性是这样的:
spring.datasource.firstDb.jdbc-url=
spring.datasource.firstDb.username=
spring.datasource.firstDb.password=
spring.datasource.secondDb.jdbc-url=
spring.datasource.secondDb.username=
spring.datasource.secondDb.password=
属性的问题是我必须定义jdbc-url而不是url,否则就会出现异常。
注。
此外,您的数据库中可能有不同的命名方案,这就是我的情况。由于Hibernate 5不支持所有以前的命名方案,我不得不使用这个答案中的解决方案——也许它也会帮助到某些人。