implementing a view resolver to find jsp in a jar

[MikeNereson]

We are trying to build up a modular system where jars contain application contexts and jsps along with the classes. Different URIs are located in different jars.

For example lets say we have a request for /monkey/home.html and another for /elephant/home.html. I need monkey to go to WEB-INF/lib/monkey-1.1.jar!/WEB-INF/jsp/monkey/home.jsp and elephant to go to WEB-INF/lib/elephant-1.1.jar!/WEB-INF/jsp/monkey/home.jsp. Then there are other's that are in the main webapps web-inf/jsp such as a request for simply home.html should be found in web-inf/jsp/home.jsp.

Any ideas on how to implement a org.springframework.web.servlet.ViewResolver to be able to find the jsp in the jar? I started something, but its not working:

 <bean id="viewResolver" class="com.retrieve.commons.viewResolver.JarViewResolver">
        <property name="cache" value="false" />
        <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
        <property name="prefix" value="/WEB-INF/jsp/" />
        <property name="suffix" value=".jsp" />
        <property name="locations">
            <map>
                <entry key="monkey" value="animals-monkey-5.2.jar"/>
                <entry key="elephant" value="animals-elephant-5.2.jar"/>
            </map>
        </property>
    </bean>

public class JarViewResolver
        extends org.springframework.web.servlet.view.InternalResourceViewResolver
{
    private String requested;
    private Map<String, String> locations = new HashMap<String, String>();

    public void setLocations(Map<String, String> locations)
    {
        this.locations = locations;
    }

    protected String getPrefix()
    {
        Set<Map.Entry<String, String>> entries = locations.entrySet();

        for (Map.Entry entry : entries)
        {
            if (requested.contains(entry.getKey().toString()))
            {
                return "/WEB-INF/lib/" + entry.getValue().toString() + "!/WEB-INF/jsp/";
            }
        }

        return super.getPrefix();
    }

    protected AbstractUrlBasedView buildView(String s)
            throws Exception
    {
        requested = s; // /elephant/Home
        return super.buildView(s);    
    }
}

Errors as:

HTTP Status 404 -The requested resource (/context/WEB-INF/lib/animal-monkey-5.2.jar!/WEB-INF/jsp/monkey/Home.jsp) is not available.

Lets assume the file is indeed in that location, in that jar, and in that web-inf jsp directory. How can I pull a resource from the jar?

Thanks.

[MikeNereson]

Any thoughts at all? Its been a few months. I need to revisit this issue again.

[Proner]

Oups... I've almost posted the same request a few hours ago... but you've much better defined the issue.

Maybe you have resolved this question by the time... any help would be appreciate.

Thanks

Steph

[MikeNereson]

Hello, Steph.

I have not solved this problem. The work that I have done towards this has been exploratory.

You already found my other post on the topic http://forum.springframework.org/showthread.php?t=65740

I think part of the solution to this particular problem is that the jsp in the jar may need to be precompiled to .class files and put into the jar. I think there is a maven plugin that can do this.

But the answer to your question here and in the other post is, No, I have not yet found a solution to creating modular web applications that allow you to add and remove web resource functionality by adding and removing jars.

I'll be sure to contact you if I find anything useful, please do the same for me ( :

Cheers.