CloudStack采用spring加载bean(cloud-framework-spring-module模块)

tanggang1740

　　CloudStackContextLoaderListener



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package org.apache.cloudstack.spring.module.web;
import java.io.IOException;
import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;
import org.apache.cloudstack.spring.module.factory.CloudStackSpringContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.web.context.ConfigurableWebApplicationContext;
import org.springframework.web.context.ContextLoaderListener;
public class CloudStackContextLoaderListener extends ContextLoaderListener {
public static final String WEB_PARENT_MODULE = "parentModule";
public static final String WEB_PARENT_MODULE_DEFAULT = "web";
private static final Logger log = LoggerFactory.getLogger(CloudStackContextLoaderListener.class);
CloudStackSpringContext cloudStackContext;
String configuredParentName;
@Override
protected ApplicationContext loadParentContext(ServletContext servletContext) {
return cloudStackContext.getApplicationContextForWeb(configuredParentName);
}
@Override
    //上下文初始化，通过servlet内容事件
public void contextInitialized(ServletContextEvent event) {
try {
cloudStackContext = new CloudStackSpringContext();
event.getServletContext().setAttribute(CloudStackSpringContext.CLOUDSTACK_CONTEXT_SERVLET_KEY, cloudStackContext);
} catch (IOException e) {
log.error("Failed to start CloudStack", e);
throw new RuntimeException("Failed to initialize CloudStack Spring modules", e);
}
configuredParentName = event.getServletContext().getInitParameter(WEB_PARENT_MODULE);
if ( configuredParentName == null ) {
configuredParentName = WEB_PARENT_MODULE_DEFAULT;
}
super.contextInitialized(event);
}
@Override
protected void customizeContext(ServletContext servletContext, ConfigurableWebApplicationContext applicationContext) {
super.customizeContext(servletContext, applicationContext);
String[] newLocations = cloudStackContext.getConfigLocationsForWeb(configuredParentName,
applicationContext.getConfigLocations());
　　　　 //设置应用到新的位置
applicationContext.setConfigLocations(newLocations);
}
}