Question

java spring MapDataSourceLookup类是作什么用的?

Answer 1

Simple DataSourceLookup implementation that relies on a map for doing lookups.
这个类依赖于查找数据源的Map!
Useful for testing environments or applications that need to match arbitrary String names to target DataSource objects.
提供 根据名字匹配数据源 的这么一种功能!
用的最多的是在多数据源中根据name配置,有点类似下面这样~~
<bean id="myds1" class="org.springframework.jndi.JndiObjectFactoryBean" destroy-method="close">
<property name="jndiName">
<value>myds1</value>
</property>
</bean>
<bean id="myds2" class="org.springframework.jndi.JndiObjectFactoryBean" destroy-method="close">
<property name="jndiName">
<value>myds2</value>
</property>
</bean>
<bean id="myds3" class="org.springframework.jndi.JndiObjectFactoryBean" destroy-method="close">
<property name="jndiName">
<value>myds3</value>
</property>
</bean>
<util:map id="ourDs">
<entry key="ds1" value-ref="myds1" />
<entry key="ds2" value-ref="myds2" />
<entry key="ds3" value-ref="myds3" />
</util:map>
<bean id="dataSourceLookup" class="org.springframework.jdbc.datasource.lookup.MapDataSourceLookup">
<constructor-arg>
<ref bean="ourDs" />
</constructor-arg>
</bean>
<bean id="myDs" class="com.huawei.nser.cache.MultiDataSource">
<property name="defaultTargetDataSource" ref="myds1" />
<property name="targetDataSources" ref="ourDs" />
<property name="dataSourceLookup" ref="dataSourceLookup" />
</bean>

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其他看懂了，这个MultiDataSource里面要完成哪些事情？