I have read some tutorials about using spring, and I've seen they speak about "spring-config.xml", but when I create a project I don't have that file, I have "application-config.xml", are they the same? Is the former the updated version of the latter? I am using Eclipse as IDE
The Spring Context only defines the concept of creating a Spring configuration where you will define spring components (beans, services, etc)
The XML itself can be named whatever you want, but in the web.xml file, you have to pass the xml name you choose to the spring context listener
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/thisXMLhaTheBestNameEver.xml</param-value>
</context-param>
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
Related
I am trying to deploy a spring web app in tomcat with log4j logging. From what I see from reading up on log4j configuration you can do it as follows -
<context-param>
<param-name>log4jConfiguration</param-name>
<param-value>/WEB-INF/webdynamo-log4j.xml</param-value>
</context-param>
<context-param>
<param-name>log4j.refresh.interval</param-name>
<param-value>120</param-value>
</context-param>
And you also need a listener for this to work -
Couple of places I have seen -
<listener>
<listener-class>
org.apache.logging.log4j.web.Log4jServletContextListener
</listener-class>
</listener>
and some places I have seen
<listener>
<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
</listener>
Wanted to understand if there is any fundamental difference in using these listeners. I see they are in different packages altogether.
I'm using Spring, but not SpringMVC in a web applcaition and gotta initialize Spring Application via web.xml
I have the standard web-project structure:
WEB-INF/applicationContext.xml
WEB-INF/web.xml
web.xml is currently contains:
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/applicationContext.xml</param-value>
</context-param>
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
But my question was caused that any listener should be bound to a servlet. In my case I don't use dispatcherServlet. How to load spring WebApplicationContext, all spring beans, etc in that case? What do I write in web.xml?
A ContextLoaderListener initializes a WebApplicationContext and stores it in the ServletContext attributes under the name referenced by WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE.
You can retrieve it that way.
servletContext.getAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE);
anywhere you have access to the ServletContext, after the ContextLoaderListener has finished executing.
As suggested by M.Deinum in the comments, this is such a popular use case that Spring has its own utility to do it:WebApplicationContextUtils.getRequiredWebApplicationContext(ServletContext).
You don't need to change anything in your web.xml.
I have created a Spring MVC project through eclipse. I believe I used some plugins to generate the project directory. I find here there configuration files.
web.xml
root-context.xml
servlet-context.xml
I am kinda of familiar with Spring MVC & its dependency injection. However I have problems understanding the last two configuration files (root-context & servlet-context).
What kind of configurations do they contain?
Also in may online examples I see mvc-dispatcher-servlet.xml. Why did eclipse not generate this xml file in my project?
[IMPORTANT] I wanted to set up strong security and user authentication for my web app. I have been following online tutorials again and they all create a seperate
xml file named spring-security.xml and add the namespace information to that file. Does it suffice if I just create this file and add the name space information? I mean
dont' I need to import this file to a main file that is scanned by Spring framework?
How do I define and where do I put spring application context.xml file and start wiring the dependencies together? Also if I define everything (all dependencies here) how is this file picked up by the framework?
Thanks,
Configuration Files
If you check your web.xml you will find both of root-context.xml and servlet-context.xml files being referred here. One used by Dispatcher Servlet and other by Context Loader Listenter. You can name your files to whatever unless they are being refereed in web.xml
Eclipse Not generating files
Every editor works its own way. some may generate full fledged project/app with both DispatcherServlet and ContextLoaderListner configured or some with only DispatcherServlet ( with minimal configutaion). Check Spring Roo it starts with basic and gives you the flexibility to generate a strong app.
mvc-dispatcher-servlet.xml is not there
Some of the thing in spring projects are convention based, for example if you are not providing any file to your DispatcherServlet in web.xml spring looks for mvc-dispatcher-servlet.xml file, and if you have provided it won't look for.
Spring Security
To Configure Spring Security you need to provide at least some configuration. But the question is where. You need to add this configuration to your web.xml only. and Hence no need to import this to any other file.
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener- class>
</listener>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/spring/spring-security.xml
</param-value>
</context-param>
<filter>
<filter-name>springSecurityFilterChain</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
<filter-name>springSecurityFilterChain</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
Where to define application context.xml
Just define it any where, configure beans in it.
You can add this file as follows:
a) Either Import this into some other configuration file like root-context.xml or servlet-context.xml
as <import resource="application-context.xml"/>
b) Add this into web.xml with ContextLoaderListner as context param
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
classpath*:META-INF/spring/application-context*.xml
classpath*:META-INF/spring/abc*.xml
</param-value>
</context-param>
I use intelliJ Idea 10.5. when i use context-param for for spring context and run project Tomcat show me blank page!! when I disable it, page show!
<context-param>
<param-name>contextLocation</param-name>
<param-value>classpath:context/applicationContext-dao.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
You need to enable log4j and see the exception Spring is throwing when you start tomcat.. Also make sure that the context file is in the war file (on the location - WEB-INF/classes/context/applicationContext-dao.xml
Ian.
I am deploying Portlets on Liferay 5.2.3 on Tomcat 6. I get this error only for one of the portlet.
java.lang.IllegalStateException: Root context attribute is not of type WebApplicationContext
I did some research and found out that Spring was instantiating a portlet application context when it need a web one. But in my web.xml I am only defining contextLoaderListner
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
And to top it off, if a different *.jar file was being looked up by Spring, then why would my other portlets get deployed except one?
After couple of redeployments I get that to a fix. Can someone put some light on?
The root cause seems to be a static variable in the portal/application server "hanging onto" an instance of a class from the portlet. Two common culprits are log4j and java logging, both of which are commonly used by application containters.
See log4j and the thread context classloader and http://logback.qos.ch/manual/loggingSeparation.html for more discussion of loggers. The suggestion is to use SLF4J with logback OR to be sure to put log4j.jar in your WAR file so it is in the right classloader (although some containers will thwart this solution).
Also, some other class that is present in the container may be the cause. Logging is just a common problem.
Sounds like you are not defining the contextConfigLocation? in web.xml you should also have something like this in addition to the contextLoaderListener:
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/applicationContext.xml
</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
Where applicationContext.xml is a normal config file for a webapp.
You should also have this in your web.xml if using spring portlet MVC:
<servlet>
<servlet-name>ViewRendererServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.ViewRendererServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ViewRendererServlet</servlet-name>
<url-pattern>/WEB-INF/servlet/view</url-pattern>
</servlet-mapping>
In your portlet.xml I guess you have something like this to specify your portlets:
<portlet>
<portlet-name>sample</portlet-name>
<portlet-class>org.springframework.web.portlet.DispatcherPortlet</portlet-class>
<supports>
<mime-type>text/html</mime-type>
<portlet-mode>view</portlet-mode>
</supports>
<portlet-info>
<title>Sample Portlet</title>
</portlet-info>
</portlet>
If you haven't already, see the spring portlet mvc reference documentation
Hope it helps.