关于继承：为什么可以继承C ++中的接口

Why can you inherit from interfaces in C++

我有一个从C++移植到Java的应用程序。有一段C++代码我觉得很奇怪。

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typedef std::string ArgName;
typedef std::map< ArgName, AnyData > ArgumentMap;

class Arguments : public ArgumentMap
{
public:
// Very important note: When read finds a numeric/set argument,
// it sets anyData.kind to Int. But STILL, it fills anyData.dString,
// just in case. So if the ArgumentMap was built by Arguments::read,
// the dString fields are all filled.
bool read( int argc, char **argv );

// remains is filled with the arguments not starting with '-'.
bool read( int argc, char **argv, std::vector<const char*>& remains );

// const if fails, erases arg if succeeds.
bool getNumericParam( const ArgName& name, int& num );

// sw is true if the switch is present. The function
// returns false if the argument value is not empty.
bool getSwitch( const ArgName& name, bool& sw );

bool getSwitchConst( const ArgName& name, bool& sw ) const;

// Returns true if the switch is present. Throws an error message if
// if the argument value is not empty.
bool getSwitchCompact( const ArgName& name );

void checkEmptyArgs() const;

};

在原始C++中，作者让他们的参数类从地图继承。这对我来说毫无意义。映射是一个接口，这意味着您不能继承它，只能实现它。这是在C++中可以做的，不能用Java做的吗？

另外，我不明白为什么要使用typedef。我读了维基百科的定义

typedef is a keyword in the C and C++ programming languages. The purpose of typedef is to
form complex types from more-basic machine types[1] and assign simpler names to such
combinations. They are most often used when a standard declaration is cumbersome,
potentially confusing, or likely to vary from one implementation to another

但我不明白为什么作者会在这里这么做。他们是想说他们想从类中继承anydata，而argumentmap应该将map作为其字段之一？