一种解决方案非常简单，可用于1级嵌套.在替代答案中可以找到一种更复杂的方法，该方法也可能允许对Maps进行更深层的嵌套.

One solution is quite simple and works for 1-level nesting. A more sophisticated approach can be found in the alternative answer which possibly also allows for deeper nesting of Maps.

代替使用接口作为类型参数，只需使用像TreeMap

Instead of using an interface as type parameter, simply use a concrete class like TreeMap

 @Parameter
 private Map<String, TreeMap> converters.

原因是在

The reason is this check in MapConverter which fails for an interface but suceeds for a concrete class:

   private static Class<?> findElementType( final Type[] typeArguments )
   {
       if ( null != typeArguments && typeArguments.length > 1 
            && typeArguments[1] instanceof Class<?> )
       {
           return (Class<?>) typeArguments[1];
       }
       return Object.class;
   }

作为旁注，它也与此 answer 相关 a>对于Maven> 3.3.x，它还可以通过将BasicComponentConfigurator子类化并将其用作Plexus组件来安装自定义转换器. BasicComponentConfigurator具有DefaultConverterLookup作为受保护的成员变量，因此可以很容易地访问以注册自定义转换器.

As a side-note, an as it is also related to this answer for Maven > 3.3.x it also works to install a custom converter by subclassing BasicComponentConfigurator and using it as a Plexus component. BasicComponentConfigurator has the DefaultConverterLookup as a protected member variable and is hence easily accessible for registering custom converters.