Making a Spring bean Applicationcontext aware
Suppose we have a webapplication with spring,
and we are initializing spring’s WebApplicationContext by configuring ContextLoaderListener in web.xml.
How can we get an instance of spring’s applicationContext object?
Possible solutions:
While configuring spring through web.xml the spring ApplicationContext object is set in the ServletContext.
To get ApplicationContext we say
ApplicationContext applicationContext = (ApplicationContext)servletContext.getAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE);
So we can get spring ApplicationContext only where ServletContext is avaliable i.e. in Servlet,ServletFilter or any implementation class of ServletContextListener.
What if we dont want to write a servletFilter or ServletContextListener .
What if we need to access a spring bean before a servletFilter or servlet is called(for authentication)and we dont want to write a ServletContextListener.
How can we obtain spring’s applicationContext in this case?
One way to achieve this would be to use the ApplicationContextAware interface provided by Spring.
Create a class which implements ApplicationContextAware. The method, “setApplicationContext(…)” gets called during the creation of this bean, providing the reference to the context. Our program should store this for a later interaction with the context.
package com.abc;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
public class ApplicationContextProvider implements ApplicationContextAware {
private static ApplicationContext applicationContext = null;
public static ApplicationContext getApplicationContext() {
return applicationContext;
}
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
/ / Assign the ApplicationContext into a static variable
this.applicationContext = applicationContext;
}
}
Initialize the new bean in applicationContext.xml
<bean id=”applicationContextProvider” class=”com.abc.ApplicationContextProvider”></bean>
Now we can call the static method, ApplicationContextProvider.getApplicationContext(), from any class in our application, to get assess to the Spring ApplicationContext.
Eclipse, i18n, Java, QA, Uncategorized
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HEllo!!
Hey, thanks so much for your solution, it was very useful in a problem that I have communicating the jaxws2.0 with the spring beans, the beans created with jaxws2.0 have the daos in null, even that spring has injected this.
Thank u.