单根层次结构
Singly rooted hierarchy单根层次结构he singly-rooted hierarchy, in object-oriented programming, is a characteristic of most (but not all) OOP-based programming languages. In most such languages, in fact, all classes inherit directly or indirectly from a single root, usually with a name similar to Object; all classes then form a common inheritance hierarchy.
单根层次结构，在面向对象编程中（但不是全部）最为典型。在大多数编程语言里，事实上，所有类直接或间接继承自一个根（单根），通常使用一个名称类似Object，所有的类，然后形成一个共同继承层次结构。
This idea was introduced first by Smalltalk, the first OOP language, and was since used in most other ones (notably Java and C#).
Smalltalk首先提出这个想法和观点，在第一个面向对象的语言里，在其他很多编程语言里也在用这个概念（特别是Java和C#）。
A notable exception is C++, where (mainly for compatibility with C and efficiency) there is no single object hierarchy. This feature is especially useful for container libraries - they only need to allow putting an Object in a container to allow objects of any class to be put in the container. Containers in C++ have been implemented with multiple inheritance, and with help of template-based generic programming by Bjarne Stroustrup.
一个显著的例外是在C + +中，其中（主要是为了与C兼容和提高效率）不存在单一的对象层次结构。 此功能是特别有用的(集装箱?)函式库-他们只需要放在一个(函式库?容器？)Object 里，允许函式库任何类的对象去请求执行。 由Bjarne Stroustrup在C ++容器已实现应用执行和多重继承，并与帮助模板为基础的通用编程。