Package com.zfabrik.springframework.web

Class ComponentParentContextContextLoaderListener

java.lang.Object

org.springframework.web.context.ContextLoader

org.springframework.web.context.ContextLoaderListener

com.zfabrik.springframework.web.ComponentParentContextContextLoaderListener

All Implemented Interfaces:

jakarta.servlet.ServletContextListener, EventListener

public class ComponentParentContextContextLoaderListener
extends org.springframework.web.context.ContextLoaderListener

This class is useful and recommended when using a Z2 declared Spring application context as a shared parent context for web applications.

It solves two problems:

1. It addresses the re-use of foreign parent contexts bug described in
   • https://jira.springsource.org/browse/SPR-5811 and
   • https://issues.springsource.org/browse/SPR-8115
   This bug is severe as it not only leads to re-use of completely unrelated application contexts but also represents a memory leak.
2. Instead of relying on the non-trivial beanRefContext.xml approach to define a bean factory that in turn retrieves an application context. this implementation retrieves parent contexts simply given a Z2 component name in the context init parameter parentContextComponentName
In order to use, add this to your web.xml file and remove the servlet context listener declaration using Spring's default implementation org.springframework.web.context:

        <listener>
                <listener-class>com.zfabrik.springframework.web.ComponentParentContextContextLoaderListener</listener-class>
        </listener>

        <context-param>
                <param-name>parentContextComponentName</param-name>
                <param-value>.. your Z2 component exposing an application context goes here... </param-value>
        </context-param>
 

Field Summary

Fields

Modifier and Type	Field	Description
static final String	PARENT_CONTEXT_COMPONENT_NAME

Fields inherited from class org.springframework.web.context.ContextLoader

CONFIG_LOCATION_PARAM, CONTEXT_CLASS_PARAM, CONTEXT_ID_PARAM, CONTEXT_INITIALIZER_CLASSES_PARAM, GLOBAL_INITIALIZER_CLASSES_PARAM

Constructor Summary

Constructors

Constructor	Description
ComponentParentContextContextLoaderListener()

Method Summary

Modifier and Type	Method	Description
protected org.springframework.context.ApplicationContext	loadParentContext(jakarta.servlet.ServletContext servletContext)

Methods inherited from class org.springframework.web.context.ContextLoaderListener

contextDestroyed, contextInitialized

Methods inherited from class org.springframework.web.context.ContextLoader

closeWebApplicationContext, configureAndRefreshWebApplicationContext, createWebApplicationContext, customizeContext, determineContextClass, determineContextInitializerClasses, getCurrentWebApplicationContext, initWebApplicationContext, setContextInitializers

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

PARENT_CONTEXT_COMPONENT_NAME

public static final String PARENT_CONTEXT_COMPONENT_NAME

See Also:

• Constant Field Values

Constructor Details

ComponentParentContextContextLoaderListener

public ComponentParentContextContextLoaderListener()

Method Details

loadParentContext

protected org.springframework.context.ApplicationContext loadParentContext(jakarta.servlet.ServletContext servletContext)

Overrides:

loadParentContext in class org.springframework.web.context.ContextLoader