动态加载 bean 到Spring Context

动态Bean的实现类 

import java.io.IOException;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.xml.ResourceEntityResolver;
import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ConfigurableApplicationContext;

/**
 *
 * This class used to dynamic loan bean to spring context during runtime
 *
 *
 */
public class DynamicLoadBean implements ApplicationContextAware{

    private ConfigurableApplicationContext applicationContext = null;
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = (ConfigurableApplicationContext)applicationContext;
    }
    public ConfigurableApplicationContext getApplicationContext() {
        return applicationContext;
    }

    /**
     * 向spring的beanFactory动态地装载bean
     * @param configLocationString 要装载的bean所在的xml配置文件位置。
spring配置中的contextConfigLocation，同样支持诸如"/WEB-INF/ApplicationContext-*.xml"的写法。
     */
    public void loadBean(String configLocationString){
        XmlBeanDefinitionReader beanDefinitionReader = new XmlBeanDefinitionReader((BeanDefinitionRegistry)getApplicationContext().getBeanFactory());
        beanDefinitionReader.setResourceLoader(getApplicationContext());
        beanDefinitionReader.setEntityResolver(new ResourceEntityResolver(getApplicationContext()));
        try {
            String[] configLocations = new String[]{configLocationString};
            for(int i=0;i<configLocations.length;i++)
                beanDefinitionReader.loadBeanDefinitions(getApplicationContext().getResources(configLocations[i]));
        } catch (BeansException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

测试类如下 

ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext("classpath:data-access-config.xml");
        DynamicLoadBean dynamicBeanLoad =(DynamicLoadBean)ctx.getBean("dynamicLoadBean");

dynamicBeanLoad.loadBean("data-access-dynamicConfig.xml");
MagazineService magezineService = (MagazineService)ctx.getBean("magazineService");

data-access-config.xml文件中包含原始的bean, data-access-dynamicConfig.xml文件中包含要动态加载的bean的配置文件。 

不要忘了把DyanmicLoanBean 配置到原始的spring context 配置文件中也就时data-access-config.xml中

<bean id="dynamicLoadBean" class="com.spring.dynamic.DynamicLoadBean">
</bean>

动态加载的bean的配置文件 

<bean id="magazineService" class="com.ibank.test.openjpa.dao.MagazineServiceImpl">
   <property name="magazineDao" ref="magazineDao"/>
</bean>

当然了动态加载的bean也可以reference 到原始的context中的bean.比如magazineDao就是在data-access-config.xml中配置的一个bean.

 

本文转自：http://elicer.iteye.com/blog/438026