使用相同类型的2个bean:Spring中的javax.sql.DataSource

Question

我正在开发一个基于Spring Boot的应用程序,我想在其中创建2个bean:一个将指向'Oracle'数据库; 另一个将指向Hive.我已将它们声明如下:

public @Bean
BoneCPDataSource metadataDataSource() {
    BoneCPDataSource boneCPDataSource = new BoneCPDataSource();
    boneCPDataSource.setDriverClass(getDriver());
    boneCPDataSource.setJdbcUrl(getJdbcUrl());
    boneCPDataSource.setUser(getUser());
    boneCPDataSource.setPassword(getPassword());
    boneCPDataSource.setMaxConnectionsPerPartition(5);
    boneCPDataSource.setPartitionCount(5);
    return boneCPDataSource;
}

public @Bean
BasicDataSource hiveDataSource() {
    BasicDataSource basicDataSource = new BasicDataSource();

    // Note: In a separate command window, use port forwarding like this:
    //
    // ssh -L 127.0.0.1:9996:<server>:<port> -l <userid> <server>
    //
    // and then login as the generic user.

    basicDataSource.setDriverClassName("org.apache.hadoop.hive.jdbc.HiveDriver");
    basicDataSource.setUrl("jdbc:hive://127.0.0.1:9996:10000/mytable");
    return basicDataSource;
}

问题是在启动时我得到了这个:

Exception in thread "main"
org.springframework.beans.factory.BeanCreationException: Error
creating bean with name
'org.springframework.boot.actuate.autoconfigure.EndpointAutoConfiguration':
Injection of autowired dependencies failed; nested exception is
org.springframework.beans.factory.BeanCreationException: Could not
autowire field: private javax.sql.DataSource
org.springframework.boot.actuate.autoconfigure.EndpointAutoConfiguration.dataSource;
nested exception is
org.springframework.beans.factory.NoUniqueBeanDefinitionException: No
qualifying bean of type [javax.sql.DataSource] is defined: expected
single matching bean but found 2: metadataDataSource,hiveDataSource

主要是因为它们都继承自javax.sql.DataSource.解决这个问题的最佳方法是什么？

---

编辑:

现在我已经宣布如下:

public @Bean (name="metadataDataSource")
BoneCPDataSource metadataDataSource() {
    BoneCPDataSource boneCPDataSource = new BoneCPDataSource();
    boneCPDataSource.setDriverClass(getDriver());
    boneCPDataSource.setJdbcUrl(getJdbcUrl());
    boneCPDataSource.setUser(getUser());
    boneCPDataSource.setPassword(getPassword());
    boneCPDataSource.setMaxConnectionsPerPartition(5);
    boneCPDataSource.setPartitionCount(5);
    return boneCPDataSource;
}

public @Bean (name="hiveDataSource")
BasicDataSource hiveDataSource() {
    BasicDataSource basicDataSource = new BasicDataSource();

    // Note: In a separate command window, use port forwarding like this:
    //
    // ssh -L 127.0.0.1:9996:<server>:<port> -l <userid> <server>
    //
    // and then login as the generic user.

    basicDataSource.setDriverClassName("org.apache.hadoop.hive.jdbc.HiveDriver");
    basicDataSource.setUrl("jdbc:hive://127.0.0.1:9996:10000/mytable");
    return basicDataSource;
}

得到了这个例外:

Exception in thread "main"
org.springframework.beans.factory.BeanCreationException: Error
creating bean with name
'org.springframework.boot.actuate.autoconfigure.EndpointAutoConfiguration':
Injection of autowired dependencies failed; nested exception is
org.springframework.beans.factory.BeanCreationException: Could not
autowire field: private javax.sql.DataSource
org.springframework.boot.actuate.autoconfigure.EndpointAutoConfiguration.dataSource;
nested exception is
org.springframework.beans.factory.NoUniqueBeanDefinitionException: No
qualifying bean of type [javax.sql.DataSource] is defined: expected
single matching bean but found 2: metadataDataSource,hiveDataSource

其他类引用这些bean如下:

公共类MetadataProcessorImpl实现MetadataProcessor {

@Autowired
@Qualifier("metadataDataSource")
BoneCPDataSource metadataDataSource;

@Controller public class HiveController {

@Autowired
@Qualifier("hiveDataSource")
BasicDataSource hiveDataSource;

Answer 1

将其中一个梁设置为@Primary,如67.2配置两个数据源一节中所述

http://docs.spring.io/spring-boot/docs/current-SNAPSHOT/reference/htmlsingle/#howto-two-datasources

Answer 2

使用时为您的bean指定不同的名称@Bean:

@Bean(name="bonecpDS")
public BoneCPDataSource metadataDataSource() {
    //...
}

@Bean(name="hiveDS")
public BasicDataSource hiveDataSource() {
    //...
}

然后,在注入bean时,使用@Qualifier并指定bean的名称:

@Component
public class FooComponent {
    @Autowired
    @Qualifier("bonecpDS")
    DataSource boneCPDataSource;
}

Answer 3

如果您想同时使用两个数据源并且它们没有主次之分，您应该DataSourceAutoConfiguration在您的应用程序上禁用@SpringBootApplication(excludes = {DataSourceAutoConfiguration.class}).

既然DataSourceAutoConfiguration会开始上课DataSourceInitializer。类中的 init 方法DataSourceInitializer需要 get DataSource。当存在多个时DataSource，系统会因获取哪个而感到困惑DataSource。

@SpringBootApplication(excludes = {DataSourceAutoConfiguration.class})意味着系统在运行应用程序时不会加载DataSourceAutoConfiguration.class。