Spring：如何从单个模板定义动态创建多个bean

Question

I have the following Spring bean for a remote web service defined in xml:

    <bean id="authWSTemplate" class="org.springframework.remoting.jaxws.JaxWsPortProxyFactoryBean" abstract="true">
       <property name="serviceInterface" value="com.example.webservices.Authentication" />
       <property name="wsdlDocumentUrl" value="${ws.root}/authentication?wsdl" />
       <property name="namespaceUri" value="http://security.webservices.example.com/" />
       <property name="serviceName" value="AuthenticationWebService" />
       <property name="portName" value="AuthenticationPort" />
       <property name="maintainSession" value="true" />
    </bean>

How do I obtain this bean template and create a concrete bean (ie supply the root property)? Can I then put the concrete bean into the Spring container?

I need numerous concrete beans pointing to different systems, so I have different root values. For this example, say there are 2 systems with roots: http://domain1.com:8001/ws and http://domain2.com:8002/ws .

Therefore I'd want 2 beans called "authWSdom1" and "authWSdom2".

I'm expecting to do this programmatically in an application initialisation block, where I'd retrieve a list of all known system implementations (this info is only known at runtime), and create a bean for each impl, cache the bean name, then my application will retrieve the appropriate bean from the Spring container when required.

Or, is there a better pattern for this? Perhaps by providing the root value in a constructor for the bean?

I'm thinking I cannot have a single bean in Spring as I need to support concurrent access across multiple end points (ie multiple users hitting domain1 and domain2 at the same time).

Answer 1

Create custom bean that implements BeanFactoryPostProcessor and InitializingBean. Use postProcessBeanFactory method to create bean:

public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
    BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory;
    String wsdlDocumentUrl = ....;
    // .......
    registry.registerBeanDefinition(YOUR_BEAN_NAME, BeanDefinitionBuilder.childBeanDefinition(
                getParentNoDomainServicBeanName(authWSTemplate)).addPropertyReference(
                "wsdlDocumentUrl", wsdlDocumentUrl).getBeanDefinition());

}

Answer 2

While I believe that Ragnor's answer is suitable if you want to dynamically create the bean in the spring container, I decided to use spring to define my own WSTemplate DTO then use a factory class to use this DTO and programmatically build (root url provided at runtime and DTO suffix value added to it) and cache the resulting JaxWS ProxyBean:

<bean id="authWSTemplate" class="com.example.WSProxyTemplate">
   <property name="serviceInterface" value="com.example.webservices.Authentication" />
   <property name="wsdlDocumentUrlSuffix" value="/authentication?wsdl" />
   <property name="namespaceUri" value="http://security.webservices.example.com/" />
   <property name="serviceName" value="AuthenticationWebService" />
   <property name="portName" value="AuthenticationPort" />
   <property name="maintainSession" value="true" />
</bean>

I like this approach as my spring config is abstracted away from the actual WS bean used. Ie if I wanted to use something other that JaxWS, then I'd simply write a different factory which used the same DTO beans. Again, this would help if I have to choose the WS implementation at runtime depending upon some system/env criteria.