spring 3.0 Custom generic converter not found though registered.Error: no matching editors or conversion strategy found

I have got the issue I posted above resolved and posting my solution here for reference.

Before posting what was causing the error, I would like to show my <servlet-name>-servlet.xml context file loaded by my application's Dispatcher Servlet.

<servlet-name>-servlet.xml

<?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:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:tx="http://www.springframework.org/schema/tx"

       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">

        <context:annotation-config />

        <context:component-scan base-package="<MY-PACKAGES>" />

        <!-- Handles GET requests for /resources/** by efficiently serving static content in the ${webappRoot}/resources dir -->
        <mvc:resources location="/resources/" mapping="/resources/**"/>

        <!--
            This tag registers the HandlerMapping and HandlerAdapter required to dispatch requests to your @Controllers. 
            In addition, it applies sensible defaults based on what is present in your classpath. Such defaults include:

            1) Using the Spring 3 Type ConversionService as a simpler and more robust alternative to JavaBeans PropertyEditors
            2) Support for formatting Number fields with @NumberFormat
            3) Support for formatting Date, Calendar, and Joda Time fields with @DateTimeFormat, if Joda Time is on the classpath 
            4) Support for validating @Controller inputs with @Valid, if a JSR-303 Provider is on the classpath 
            5) Support for reading and writing XML, if JAXB is on the classpath 
            6) Support for reading and writing JSON, if Jackson is on the classpath   
         -->

        <mvc:annotation-driven/>

        <mvc:interceptors>
          <bean class="org.springframework.orm.hibernate3.support.OpenSessionInViewInterceptor">
              <property name="sessionFactory">
                  <ref bean="sessionFactory"/>
              </property>
              <property name="singleSession" value="false" />
          </bean>
        </mvc:interceptors>

        <!-- 
             Without the following adapter, we'll get a "Does your handler implement a supported interface like Controller?"
             This is because mvc:annotation-driven element doesn't declare a SimpleControllerHandlerAdapter
             For more info
             See http://stackoverflow.com/questions/3896013/no-adapter-for-handler-exception
             See http://forum.springsource.org/showthread.php?t=48372&highlight=UrlFilenameViewController    
        -->
        <bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter" />

        <!-- 
              org.springframework.web.servlet.view.ResourceBundleViewResolver
              The bundle is typically defined in a properties file, 
              located in the class path. The default bundle basename is "views". 
        -->
        <bean id="viewResolver" class="org.springframework.web.servlet.view.ResourceBundleViewResolver">
             <property name="basename" value="views" />
        </bean>

</beans>

As can be seen in above file I have used <mvc:annotation-driven/> which by default activates the org.springframework.format.support.FormattingConversionService. I needed an instance of org.springframework.core.convert.support.GenericConversionService instead, to which I am registering my custom converter StringToMapConverter (shown in my first post) using ConverterConfig (shown in my first post).

The value of property, at spring container initialization time, org.springframework.web.bind.support.ConfigurableWebBindingInitializer.setConversionService(ConversionService) was getting set as the instance of org.springframework.format.support.FormattingConversionService instead of org.springframework.core.convert.support.GenericConversionService to which i registered my custom converter and thus the error was thrown that no matching editors or conversion strategy found.

However I don't need the formatting conversion service in my application as of now and just wanted to register my custom converter.Thus to achieve my goal I used the updated code shown below:

Updated <servlet-name>-servlet.xml

<?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:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:tx="http://www.springframework.org/schema/tx"

       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">

        <context:annotation-config />

        <context:component-scan base-package="<MY-PACKAGES>" />

        <!-- Handles GET requests for /resources/** by efficiently serving static content in the ${webappRoot}/resources dir -->
        <mvc:resources location="/resources/" mapping="/resources/**"/>

        <!--
            This tag registers the HandlerMapping and HandlerAdapter required to dispatch requests to your @Controllers. 
            In addition, it applies sensible defaults based on what is present in your classpath. Such defaults include:

            1) Using the Spring 3 Type ConversionService as a simpler and more robust alternative to JavaBeans PropertyEditors
            2) Support for formatting Number fields with @NumberFormat
            3) Support for formatting Date, Calendar, and Joda Time fields with @DateTimeFormat, if Joda Time is on the classpath 
            4) Support for validating @Controller inputs with @Valid, if a JSR-303 Provider is on the classpath 
            5) Support for reading and writing XML, if JAXB is on the classpath 
            6) Support for reading and writing JSON, if Jackson is on the classpath   
         -->

         <!-- 
              We just require the converter feature not the formatting feature.Thus
              registering only the org.springframework.core.convert.support.GenericConversionService and 
              not org.springframework.format.support.FormattingConversionService which
              <mvc:annotation-driven> activates by default.Also we are registering
              a custom converter using the com.flightnetwork.cars.controller.util.ConverterConfig
              class 
         -->
        <!-- Added this to resolve my issue -->
        <mvc:annotation-driven conversion-service="conversionService"/> 

        <mvc:interceptors>
          <bean class="org.springframework.orm.hibernate3.support.OpenSessionInViewInterceptor">
              <property name="sessionFactory">
                  <ref bean="sessionFactory"/>
              </property>
              <property name="singleSession" value="false" />
          </bean>
        </mvc:interceptors>

        <!-- 
             Without the following adapter, we'll get a "Does your handler implement a supported interface like Controller?"
             This is because mvc:annotation-driven element doesn't declare a SimpleControllerHandlerAdapter
             For more info
             See http://stackoverflow.com/questions/3896013/no-adapter-for-handler-exception
             See http://forum.springsource.org/showthread.php?t=48372&highlight=UrlFilenameViewController    
        -->
        <bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter" />

        <!-- 
              org.springframework.web.servlet.view.ResourceBundleViewResolver
              The bundle is typically defined in a properties file, 
              located in the class path. The default bundle basename is "views". 
        -->
        <bean id="viewResolver" class="org.springframework.web.servlet.view.ResourceBundleViewResolver">
             <property name="basename" value="views" />
        </bean>

        <!-- Added this to resolve my issue -->
        <bean id="conversionService" class="org.springframework.context.support.ConversionServiceFactoryBean"/>
</beans>

Updated ConverterConfig.java

    import java.util.Collections;

    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.context.annotation.DependsOn;
    import org.springframework.core.convert.ConversionService;
    import org.springframework.core.convert.converter.ConverterRegistry;
    import org.springframework.core.convert.support.ConversionServiceFactory;

    @Configuration
    public class ConverterConfig {

        @Autowired
        private ConversionService conversionService;

        @Autowired
        private ConverterRegistry converterRegistry;

        @Bean
        @DependsOn(value="conversionService")
        public StringToMapConverter stringToMapConverter() {
            StringToMapConverter stringToMapConverter = new StringToMapConverter();
            stringToMapConverter.setConversionService(this.conversionService);

            ConversionServiceFactory.registerConverters(
                    Collections.singleton(stringToMapConverter), this.converterRegistry);

            return stringToMapConverter;
        }
    }

I was having a similar problem that resulted in the same exception message:

no matching editors or conversion strategy found

On inspection, the conversionService used in the binding appeared to be a default, rather than the one I had configured to include my custom converter.

It turned out that I had declared <mvc:annotation-driven> in two different files, and the declaration without conversion-service="conversionService" was taking precedence.

Those suffering from this symptom may just want to check their config, before spending hours slamming head against desk.

I would try changing your XML to

<bean id="conversionService" class="org.springframework.context.support.ConversionServiceFactoryBean">
    <property name="converters">
        <set>    
            <bean id="stringToMapConverter" class="com.myapp.util.StringToMapConverter" />
        </set>
    </property>
</bean>

I have something pretty much identical in my config and it works fine (I don't know if the issue might be the missing set tags or it not handling bean ref's)

In case you want to use default formatters with new converters instead of overriding it, you can do like this.

<bean id="conversionService" class="org.springframework.format.support.FormattingConversionServiceFactoryBean">
    <property name="converters">
        <set>
            <bean class="path.to.SomeConverter"/>
        </set>
    </property>
</bean>

<mvc:annotation-driven conversion-service="conversionService" />

Here is the document.