Spring：如何在运行时管理使用BeanFactoryPostProcessor创建的数据源？

Question

I am working on a projet using Spring Data JPA.

I've managed to dynamicly create datasource with BeanFactoryPostProcessor and switch to the desired one when i log in using AbstractRoutingDataSource .

Now what i want to do in runtime is to:

1. Get the map of the dynamically datasources with BeanFactoryPostProcessor
2. Create a new datasource
3. Put the recently created datasource in the map along with the others

springContext-jpa.xml

<?xml version="1.0" encoding="UTF-8"?> 
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:jpa="http://www.springframework.org/schema/data/jpa"
............
>
<!-- 
...
...
Spring Data JPA config 
...
...
-->

<!--    Parent abstract Datasource -->
<bean id="BasicdsCargestWeb" class="org.apache.commons.dbcp.BasicDataSource">
    <property name="driverClassName" value="${jdbc.driverClassName}"></property>
    <property name="username" value="${jdbc.username}"></property>
    <property name="password" value="${jdbc.password}"></property>
</bean>

<!--  Generic Datasource   -->
<bean id="dsCargestWeb" class="com.cargest.custom.CargestRoutingDataSource">
    <property name="targetDataSources">
        <map>

        </map>
    </property>
    <property name="defaultTargetDataSource" ref="cargestnet1ds" />
</bean>

</beans>

DatasourceRegisteringBeanFactoryPostProcessor.java

@Component 
class DatasourceRegisteringBeanFactoryPostProcessor implements BeanFactoryPostProcessor { 

public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) {

    // this is my list of Datasources 
    List<Database> dbs = new ArrayList<Database>();

    /*
     * Hidden code, here i get my list of Datasources 
     */

    BeanDefinitionRegistry factory = (BeanDefinitionRegistry) beanFactory;
    BeanDefinitionBuilder datasourceDefinitionBuilder;

    for (Database db : dbs) {
        datasourceDefinitionBuilder = BeanDefinitionBuilder
                .childBeanDefinition("BasicdsCargestWeb") 
                .addPropertyValue("url", db.getUrl()+db.getName()+"?autoReconnect=true");

        factory.registerBeanDefinition("cargestnet"+db.getId()+"ds",
                datasourceDefinitionBuilder.getBeanDefinition());
    }


    // Configure the dataSource bean properties 
    MutablePropertyValues mpv = factory.getBeanDefinition("dsCargestWeb").getPropertyValues();

    // Here you can set the default dataSource 
    mpv.removePropertyValue("defaultTargetDataSource");
    mpv.addPropertyValue("defaultTargetDataSource", 
        new RuntimeBeanReference("cargestnet1ds")); 

    // Set the targetDataSource properties map with the list of connections 
    ManagedMap<String, RuntimeBeanReference> mm = (ManagedMap<String, RuntimeBeanReference>) mpv.getPropertyValue("targetDataSources").getValue();
    System.out.println("list size "+mm.size());

    mm.clear();

    for (Database db : dbs) {
         mm.put(db.getId().toString(), new RuntimeBeanReference("cargestnet"+db.getId()+"ds"));
    }
} 
} 

The problem is that the BeanFactoryPostProcessor class is using ConfigurableListableBeanFactory as a beanFactory.

I need to access that same beanFactory from another class (in runtime) in order to modify my map of datasources (dsCargestWeb --> targetDataSources --> map).

Thanks

Answer 1

I think you could try the following architecture :

• a factory bean creates the initial map of DataSourceS
• the AbstractRoutingDataSource implementation holds the map of the DataSourceS , and is initially injected with above factory bean

That way, if you later need to add a new DataSource , you can either get the map from the AbstractRoutingDataSource implementation and add it directly to it, or put a method in the AbstractRoutingDataSource implementation to add a new DataSource .

As a variant from the above, you can create a similar AbstractRoutingDataSource implementation, and another bean injected with it, that in its init-method computes the DataSourceS map and strores it in the routing datasource.

Answer 2

With RuntimeBeanReference and ManagedSet , you can set a runtime set to your beanDefine . This is the proper way to use these:

ManagedSet<RuntimeBeanReference> processorSet = new ManagedSet<RuntimeBeanReference>();
    for (String processorBeanName : processorBeanNames) {
        processorSet.add(new RuntimeBeanReference(processorBeanName));
    }
beanDefine.getPropertyValues().addPropertyValue(new PropertyValue(key, value));