I am learning spring MVC, Can someone tell me when WebApplicationCotext gets initialized? and who is responsible to initialize WebApplicationContext?
i think it is initialized in the first time when the app runs, here is my log when spring webapp starts, the server container is reponsible to it?
Related
We have a requirement which we can change the spring context XML file on the fly and then reload it manually, we can successfully load/reload multiple application context by the following code
ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext(contextPath);
by using the above code, a new application context will be created on demand, however when we try to use the same way to create a WebApplicaitonContext on demand, we failed.
My question is there any way that we can create multiple WebApplicaitonContext on demand after SpringBoot application starts? or we can only have one webapplicationContext and my idea won't be able to be reached?
thanks
I am developing a java web application in which I want to cache all the data present in a table during server start up.
Also if there are any changes in DB values, I wish to refresh the cache (without restarting the server).
I am looking for some material in spring which may help me in achieving that. But I am not able to figure it out.
Please help how can I achieve the same. Also I would like to initialize some beans on server start up.
To start with read the following docs which will get you started.
Refer to Spring document http://static.springsource.org/spring/docs/3.2.x/spring-framework-reference/html/cache.html
Also check this simple tutorial http://viralpatel.net/blogs/cache-support-spring-3-1-m1/
Regarding your bean initialization you can use #PostConstruct annotation on a method of the bean class. Spring will call that method after the bean is constructed.
The application that your planning to build wouldnt be an easy one. In my experience, creating an application like that would require a knowledge of the following:
1. Spring
2. Ehcache
3. JMX
4. Servlet Listeners
We are using cucumber-jvm to write an integration test layer in our application. One of the challenges we are finding is managing the database between the tests and the web application.
A typical scenario is that we want to persist some entities in a Given step of a scenario, then perform some actions on the user interface that may, in turn, persoist more entities. At the end, we want to clean the database. Because the cucumber-jvm tests are in one jvm and the web application is running in another jvm we cannot share a transaction (at least in a way of which I am aware) so the database must be cleaned manually.
My initial thought was to use an Embedded Tomcat server running off of an embedded in-memory database (HSQLDB) in the same JVM as the cucumber-jvm test. This way we might be able to share a single spring container, and by extension a single transaction, from which all objects could be retrieved.
During my initial tests it looks like Spring gets loaded and configured twice: once when the test starts and the cucumber.xml is read, and a second time when the embedded tomcat starts and the web application reads its applicationContext.xml. These appear to be in two completely separate containers because if I try to resolve an object in one container that is specified in the other container then it doesn't resolve. If I duplicate my configuration then I get errors about duplicate beans with the same id.
Is there a way that I can tell Spring to use the same container for both my test application and the embedded tomcat?
I'm using Spring 3.2.2.GA and Embedded Tomcat 7.0.39 (latest versions of both libraries).
Am I crazy? Do I need to provide more technical details? Apologies if I use some incorrect terminology.
Thanks
p.s. If my problem seems familiar to you and you can suggest an alternative solution to the one I am trying, please let me know!
Jeff,
It is normal that spring is loaded twice. There are two places where two spring contexts are created:
In the servlet container listener org.springframework.web.context.ContextLoaderListener that is configured in web.xml. This one reads its configuration from the file set by the context-param contextConfigLocation.
In the implementation of ObjectFactory provided by cucumber-spring plugin cucumber.runtime.java.spring.SpringFactory. This one reads its configuration from cucumber.xml.
The two spring contexts are totally different and their instances are kept in two different places. As a servlet context attribute for the former and kept by the JavaBackend for the latter.
When starting the embedded tomcat, it is possible to get access to the servlet context and thus set ourself the spring context used bt tomcat with the one from cucumber. But, spring has a special class called WebApplicationContext for context used in a servlet container. The cucumber SpringFactory on other hand creates its context through ClassPathXmlApplicationContext. So unless there is a way to specify the type of application context from the xml config, we will have to provide an ObjectFactory that shoots a WebApplicationContext.
What we can do is to have two web.xml. One for the normal and one for the test. For the test, we use our version of the ContexLoader listener.
When i am running my application it give me this exception:-
Exception sending context initialized event to listener instance of class
org.springframework.web.util.Log4jConfigListener
java.lang.ExceptionInInitializerError
But this problem is not permanent. If i remove the log4j entries from web.xml and restart p.c and then again add log4j entries and start the server, then the application works fine.
I noticed that when the application is deployed and when i undeploy and again deploy the same application, this problem emerge.
Please help me ........ i am facing this problem from 3 months...
I just investigated it a little and have found the similar issue:
It causes when multiple jar file for log4j is available to application.
From web/application server and from build path(Included from other
path rather than web/application server)
You can see the entire thread here:
http://www.coderanch.com/t/551933/Spring/Exception-sending-context-initialized-event
looks like this is your problem.
I'm currently experiencing problems with a JPATransactionManager in a J2SE application.
The latest request was not properly saved in the database (surely a problem of cache).
This seems to be normal because the exit of the program does not seem to "cleanly" exit all Bean of the spring application context.
Do you know if there's a method of a clean shutdown a Spring context before exiting ?
Thank you in advance.
Checkout Spring Reference manual on this topic.
Basically you need to call registerShutdownHook() on the application context.