How to do spring request parameter conversion

Question

In a Spring 3 based web (portlet) application I have a controller with a method like this:

@RenderMapping
public ModelAn         


        

Answer 1

Implement a WebArgumentResolver:

public class MyArgumentResolver implements WebArgumentResolver
{
    @Override
    public Object resolveArgument(MethodParameter methodParameter,
            NativeWebRequest webRequest) throws Exception
    {
        Class paramType = methodParameter.getParameterType();
        if (paramType == MyClass.class)
        {
            String parameterName = methodParameter.getParameterName();
            String stringParameter = webRequest.getParameter(parameterName);
            return convert(stringParameter);
        }
        return UNRESOLVED;
    }
}

And register it in your applicationContext.xml:

This works and even has the advantage of allowing parameter conversion that is based on multiple method parameters.