Accessing private/protected method with generic type using reflection

Question

I have a class with a validate method that contains generic type

public class Foo{
private <T> validateThis(T objectToValidate)
{
Set<ConstraintViolation<T>> constraintViolations;
try
        {
            constraintViolations = validator.validate(objectToValidate);
        }
        catch(RuntimeException re)
        {
            throw new HttpStatusUnprocessableEntityException("Unexpected problem occurred);
        }  
} 

however I want to access this method using reflection (i.e for unit testing ) but when I try

Method method = 
Foo.class.getDeclaredMethod("validateThis",ParameterizedType.class);
method.setAccessible(true);

I am getting

java.lang.NoSuchMethodException:Foo.validateThis(java.lang.reflect.ParameterizedType)