Polymorphism, from Greek for “many shapes,” allows objects of different classes to be treated as objects of a common superclass. It enables a single interface, such as a method name, to be used for a general class of actions. The specific action is determined by the exact type of the object at runtime. This is often achieved through method overriding.
Polymorphism is a powerful concept that allows for writing flexible and decoupled code. The most common form in OOP is subtype polymorphism, which is enabled by inheritance and 方法 overriding. When a subclass provides a specific implementation for a method that is already defined in its superclass, it is called overriding. A variable of the superclass type can refer to an object of any of its subclasses. When a method is called on this variable, the version of the method that gets executed is the one belonging to the object’s actual class, not the variable’s type. This decision is made at runtime, a process known as dynamic dispatch or late binding.
For example, consider a superclass ‘Shape’ with a method ‘calculateArea()’. Subclasses like ‘Circle’ and ‘Rectangle’ can inherit from ‘Shape’ and provide their own specific implementations of ‘calculateArea()’. A program can then have a list of ‘Shape’ objects, containing both ‘Circle’ and ‘Rectangle’ instances. When iterating through the list and calling ‘calculateArea()’ on each element, the correct formula will be used for each shape automatically. This eliminates the need for long ‘if-else’ or ‘switch’ statements to check the type of each object, leading to cleaner, more extensible code. New shapes can be added to the system without modifying the code that processes them.
迎接新挑战
机械工程师、项目、工艺工程师或研发经理
可在短时间内接受新的挑战。
通过 LinkedIn 联系我
塑料金属电子集成、成本设计、GMP、人体工程学、中高容量设备和耗材、精益制造、受监管行业、CE 和 FDA、CAD、Solidworks、精益西格玛黑带、医疗 ISO 13485
(如果日期不详或不相关，例如 "流体力学"，则对其显著出现的时间作了四舍五入的估计）。
相关发明、创新和技术原理
{{标题}}
{%，如果摘录 %}{{ 摘录 | truncatewords：55 }}
{% endif %}
