The way you describe the problem, it sounds like this is a good case for using inheritance. The rule of thumb is to use inheritance if A is-a B and to use composition if A is-implemented-in-terms-of B.
The recommendation to prefer composition to inheritance does not mean "never ever use inheritance". It means use inheritance appropriately. For example, if you write a Stack class in C++ using an std::vector, you don't want to derive Stack from vector. A Stack is not a vector, it is implemented-in-terms-of a vector, which implies composition. You also want to avoid creating deep class hierarchies, because that results in tight coupling.
In your case, however, inheritance seems like an obvious choice.
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从您描述问题的方式来看，这听起来像是使用继承的一个很好的例子。经验法则是，如果 A 是 B，则使用继承；如果 A 是根据 B 实现的，则使用组合。
优先使用组合而不是继承的建议并不意味着“永远不要使用继承”。这意味着适当地使用继承。例如，如果您使用
std::vector在 C++ 中编写Stack类，则您不希望从Stack派生>矢量。Stack不是一个向量，它是用向量实现的，这意味着组合。您还希望避免创建深层类层次结构，因为这会导致紧密耦合。然而，就您而言，继承似乎是一个显而易见的选择。
The way you describe the problem, it sounds like this is a good case for using inheritance. The rule of thumb is to use inheritance if A is-a B and to use composition if A is-implemented-in-terms-of B.
The recommendation to prefer composition to inheritance does not mean "never ever use inheritance". It means use inheritance appropriately. For example, if you write a
Stackclass in C++ using anstd::vector, you don't want to deriveStackfromvector. AStackis not avector, it is implemented-in-terms-of avector, which implies composition. You also want to avoid creating deep class hierarchies, because that results in tight coupling.In your case, however, inheritance seems like an obvious choice.