org.springframework.beans.BeanInstantiationExcepti on

[Nigel W]

Hi,

I am trying to use "spring mobile" but I am having little success so far.

I have made the following changes to my exisiting Spring 3.0 MVC project.

POM - move

spring-orm
spring-context
spring-beans
spring-core
spring-webmvc
spring-web
spring-jdbc
spring-context-support

org.springframework dependancies to 3.1.0.M1.


change:

<?xml version="1.0" encoding="UTF-8" ?>
<beans xmlns="http://www.springframework.org/schema/beans" 
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
       xmlns:mvc="http://www.springframework.org/schema/mvc" 
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">
       
<!--  Configures the @Controller programming model 
  --> 
  <mvc:annotation-driven />
    
</beans>

to

<?xml version="1.0" encoding="UTF-8" ?>
<beans xmlns="http://www.springframework.org/schema/beans" 
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
       xmlns:mvc="http://www.springframework.org/schema/mvc" 
       xmlns:device="http://www.springframework.org/schema/mobile/device"  
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd http://www.springframework.org/schema/mobile/device http://www.springframework.org/schema/mobile/device/spring-mobile-device-1.0.xsd">
       <!--  When went to Spring 3.1 change line above to 3.1 -->
       
<!--  Configures the @Controller programming model --> 
  <mvc:annotation-driven>
     <mvc:argument-resolvers>
        <bean class="org.springframework.mobile.device.DeviceWebArgumentResolver" />
     </mvc:argument-resolvers>
   </mvc:annotation-driven>
   
  <mvc:interceptors>
     <!-- On pre-handle, resolve the device that originated the web request -->
     <bean class="org.springframework.mobile.device.DeviceResolverHandlerInterceptor" />
  </mvc:interceptors>
 		
</beans>

In my controller I am trying to bind 'Device'

 public String showUserPage(Principal principal,
		@RequestParam(value="userid") Long userid,
                             ModelMap model,
                             Device device){

but I am getting the following exception.

org.springframework.beans.BeanInstantiationExcepti on: Could not instantiate bean class [org.springframework.mobile.device.Device]: Specified class is an interface


Any help greatly appreciated.

[Keith Donald]

Hmm. for some reason it seems the DeviceWebArgumentResolver is not getting picked up. Make sure you don't have any other AnnotationMethodHandlerAdapter beans floating around from your existing app. You might want to set a breakpoint on setCustomWebArgumentResolvers method of that class and see what gets injected there. Also I'd recommend referring to the lite-showcase sample app.

[Nigel W]

Thanks again,

I have used the sample but as you correct pointed out I also had.

<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping" /> 
   

   <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" >
      <property name="messageConverters">
         <list>
            <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter" />
         </list>
      </property> 
   </bean

I have removed AnnotationMethodHandlerAdapter

and used

<mvc:annotation-driven>
     <mvc:argument-resolvers>
        <bean class="org.springframework.mobile.device.DeviceWebArgumentResolver" />
     </mvc:argument-resolvers>
     <mvc:message-converters>
        <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter" />
     </mvc:message-converters>
   </mvc:annotation-driven>

This seems to work.

I assume I can/should leave DefaultAnnotationHandlerMapping ?

[Nigel W]

Also another question - does LiteDeviceResolver find the IPad as 'mobile' ?

[Nigel W]

Realising the answer to my own question about IPADs (ie. will not be seen a 'mobile').

I decided to move to WURFL.

So I changed to:

  <mvc:interceptors>
        <!-- On pre-handle, use WURFL to detect the device that originated the web request -->
        <bean class="org.springframework.mobile.device.DeviceResolverHandlerInterceptor">
            <constructor-arg>
            	<!-- Inject a WurflDeviceResolver that populates its device repository from the specified file locations -->
                <device:wurfl-device-resolver root-location="/WEB-INF/wurfl/wurfl-2.0.30.zip" patch-locations="/WEB-INF/wurfl/web_browsers_patch.xml" />
            </constructor-arg>		
        </bean>
    </mvc:interceptors>

Having set up the zip and xml files.

Changed:

public String showUserPage(Principal principal,
		        @RequestParam(value="userid") Long userid,
                                    ModelMap model,
                                    Device device){

file to

import net.sourceforge.wurfl.core.Device;

but I am now getting:

org.springframework.beans.BeanInstantiationExcepti on: Could not instantiate bean class [net.sourceforge.wurfl.core.Device]: Specified class is an interface


My mvc:annotation-driven is:

<mvc:annotation-driven>
     <mvc:argument-resolvers>
        <bean class="org.springframework.mobile.device.DeviceWebArgumentResolver" />
     </mvc:argument-resolvers>
     <mvc:message-converters>
        <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter" />
     </mvc:message-converters>
   </mvc:annotation-driven>

I appear to have a binding issue.

Again any help appreciated.

[Keith Donald]

If you're using mvc:annotation-driven, you should not have DefaultAnnotationHandlerMapping or AnnotationMethodHandlerAdapter registered manually: this element registers them for you. Please refer to the wurfl-showcase sample and test it out and see how it's different then yours.

Keith

[Nigel W]

Thanks again.

Moving forward but still a problem.

What I am confused about - and the WURFL showcase does not cover this - is for the WURFL case how do you "inject the Device into your @Controller".

I have this working for the non-WURFL case but cannot seem to get it to work when I move to the WURFL case.

[Keith Donald]

Well, the WURFL showcase shows injection of a SitePreference, which is done using the same WebArgumentResolver machinery that the DeviceWebArgumentResolver uses. Something has to be wrong with your configuration. Fundamentally, a DeviceWebArgumentResolver MUST be registered with the AnnotationMethodHandlerAdapter that is used to invoke @Controllers dispatched by the DispatcherServlet. Having a duplicate AnnotationMethodHandlerAdapter floating around in your context that is not configured properly can definitely cause this problem.

You might want to try the following test:
- Take wurfl-showcase and try injecting a Device into a @Controller method. It should fail.
- Add DeviceWebArgumentResolver to the set of web-argument-resolvers, alongside SitePreferenceWebArgumentResolver, and try your @Controller test again. It should work.

Something has to be wrong with your configuration somewhere.

[Nigel W]

Found the issue - thanks for all the help - I had not noticed that I needed to change.

public String showUserPage(Principal principal,
		        @RequestParam(value="userid") Long userid,
                                    ModelMap model,
                                    Device device){

to

public String showUserPage(Principal principal,
		        @RequestParam(value="userid") Long userid,
                                    ModelMap model,
                                    WurflDevice device){

Note: An update to the 'spring mobile' documentation might be useful ?

[Keith Donald]

WurflDevice is not required there, a org.springframework.mobile.Device reference will work fine as long as the DeviceWebArgumentResolver is registered properly. You can review the code of DeviceWebArgumentResolver to see this for yourself. Of course, if you need a WurflDevice, you can inject it as well.

Keith