org.springframework.web.jsf: abstract public class: FacesContextUtils

org.springframework.web.jsf
abstract public class: FacesContextUtils [javadoc | source]

java.lang.Object
   org.springframework.web.jsf.FacesContextUtils

Convenience methods to retrieve the root WebApplicationContext for a given FacesContext. This is e.g. useful for accessing a Spring context from custom JSF code.

Analogous to Spring's WebApplicationContextUtils for the ServletContext.

Also see:

org.springframework.web.context.ContextLoader

org.springframework.web.context.support.WebApplicationContextUtils

author: Juergen - Hoeller

since: 1.1 -

Method from org.springframework.web.jsf.FacesContextUtils Summary:
getRequiredWebApplicationContext, getSessionMutex, getWebApplicationContext

Methods from java.lang.Object:
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from org.springframework.web.jsf.FacesContextUtils Detail:
public static WebApplicationContext getRequiredWebApplicationContext(FacesContext fc) throws IllegalStateException { WebApplicationContext wac = getWebApplicationContext(fc); if (wac == null) { throw new IllegalStateException("No WebApplicationContext found: no ContextLoaderListener registered?"); } return wac; } Find the root WebApplicationContext for this web app, which is typically loaded via ContextLoaderListener or ContextLoaderServlet. Will rethrow an exception that happened on root context startup, to differentiate between a failed context startup and no context at all.
public static Object getSessionMutex(FacesContext fc) { Assert.notNull(fc, "FacesContext must not be null"); ExternalContext ec = fc.getExternalContext(); Object mutex = ec.getSessionMap().get(WebUtils.SESSION_MUTEX_ATTRIBUTE); if (mutex == null) { mutex = ec.getSession(true); } return mutex; } Return the best available mutex for the given session: that is, an object to synchronize on for the given session. Returns the session mutex attribute if available; usually, this means that the HttpSessionMutexListener needs to be defined in `web.xml`. Falls back to the Session reference itself if no mutex attribute found. The session mutex is guaranteed to be the same object during the entire lifetime of the session, available under the key defined by the `SESSION_MUTEX_ATTRIBUTE` constant. It serves as a safe reference to synchronize on for locking on the current session. In many cases, the Session reference itself is a safe mutex as well, since it will always be the same object reference for the same active logical session. However, this is not guaranteed across different servlet containers; the only 100% safe way is a session mutex.
public static WebApplicationContext getWebApplicationContext(FacesContext fc) { Assert.notNull(fc, "FacesContext must not be null"); Object attr = fc.getExternalContext().getApplicationMap().get( WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE); if (attr == null) { return null; } if (attr instanceof RuntimeException) { throw (RuntimeException) attr; } if (attr instanceof Error) { throw (Error) attr; } if (!(attr instanceof WebApplicationContext)) { throw new IllegalStateException("Root context attribute is not of type WebApplicationContext: " + attr); } return (WebApplicationContext) attr; } Find the root WebApplicationContext for this web app, which is typically loaded via ContextLoaderListener or ContextLoaderServlet. Will rethrow an exception that happened on root context startup, to differentiate between a failed context startup and no context at all.

Method from org.springframework.web.jsf.FacesContextUtils Detail:

 public static WebApplicationContext getRequiredWebApplicationContext(FacesContext fc) throws IllegalStateException {
		WebApplicationContext wac = getWebApplicationContext(fc);
		if (wac == null) {
			throw new IllegalStateException("No WebApplicationContext found: no ContextLoaderListener registered?");
		}
		return wac;
}

Will rethrow an exception that happened on root context startup, to differentiate between a failed context startup and no context at all.

 public static Object getSessionMutex(FacesContext fc) {
		Assert.notNull(fc, "FacesContext must not be null");
		ExternalContext ec = fc.getExternalContext();
		Object mutex = ec.getSessionMap().get(WebUtils.SESSION_MUTEX_ATTRIBUTE);
		if (mutex == null) {
			mutex = ec.getSession(true);
		}
		return mutex;
}

Returns the session mutex attribute if available; usually, this means that the HttpSessionMutexListener needs to be defined in web.xml. Falls back to the Session reference itself if no mutex attribute found.

The session mutex is guaranteed to be the same object during the entire lifetime of the session, available under the key defined by the SESSION_MUTEX_ATTRIBUTE constant. It serves as a safe reference to synchronize on for locking on the current session.

In many cases, the Session reference itself is a safe mutex as well, since it will always be the same object reference for the same active logical session. However, this is not guaranteed across different servlet containers; the only 100% safe way is a session mutex.

 public static WebApplicationContext getWebApplicationContext(FacesContext fc) {
		Assert.notNull(fc, "FacesContext must not be null");
		Object attr = fc.getExternalContext().getApplicationMap().get(
				WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE);
		if (attr == null) {
			return null;
		}
		if (attr instanceof RuntimeException) {
			throw (RuntimeException) attr;
		}
		if (attr instanceof Error) {
			throw (Error) attr;
		}
		if (!(attr instanceof WebApplicationContext)) {
			throw new IllegalStateException("Root context attribute is not of type WebApplicationContext: " + attr);
		}
		return (WebApplicationContext) attr;
}

Will rethrow an exception that happened on root context startup, to differentiate between a failed context startup and no context at all.