how to achieve polymorphism in java

object, positioned in the method, followed by an exception object, equivalent to the effect of returnThrows: Indicates that the exception method is thrown out of () {}, followed by multiple exceptionsSimply explain the polymorphism in the following Java:　　The role of polymorphism: to eliminate the coupling relationship between types. (Coupling relationship refer

reference to child class object 2. To achieve polymorphism: Three elements to achieve polymorphism: Write a parent class and subclass with an inheritance relationship;Subclasses override the parent class method;Use the parent class's reference to point to the object of the child class;

the system in order to dynamically determine the object referred to by the method, so also known as run-time polymorphism. Dynamic polymorphism is implemented by overriding a member method of the same name in the parent class whose invocation rules are called according to the type of the object when it is not defined at the time of instantiation, and corresponding to the member method of the same name in t

have the same characteristics (attributes) and behaviors (methods), the same parts can be extracted and placed into a class as the parent class, and the other two classes inherit the parent class.Inheritance implements an object-oriented principle: Write Once,only once (written once, and written once3, how to achieve inheritance?In the Java language, the extends (extended) keyword is used to represent a cl

Polymorphism of three object-oriented features -- Java note (7)Polymorphism: the type of an object that has multiple forms of compilation is determined by the type used to declare the variable, the type of the runtime is determined by the object that is actually assigned to the variable. If the compilation type and runtime type are different, there will be a mult

Java Study Notes 11 (Object-Oriented 4: Polymorphism) and java Study Notes Polymorphism: Example: Describes multiple forms of a thing. For example, the Student class inherits the Person class. A Student object is both Student and Person. Polymorphism is: the parent class ref

conditions for ④ to achieve polymorphism?1, the existence of inheritance (inheritance is the basis of polymorphism, no inheritance there is no polymorphism)2, subclasses overriding the parent class method (polymorphic call subclasses after overriding the method)3. Parent class reference variable points to subclass obj

Java (1)-interfaces, inheritance and polymorphism, java (advanced tutorial) The previous "class and object" was removed from the home page and asked if it was suspected that the Notes could not be posted on the home page. Alas, I felt sorry for myself for a few seconds. It seems that my level is not yet in place, all are written as "Notes. Alas, at present, there

Briefly summarizeEncapsulation-that is, extracting the same code from many classes in a class.The benefit is the reuse of code and security .Inheritance-reduces the writing of the Code.Its benefits are also the reuse of code .Polymorphic-The different sub-class objects are considered as the parent class, you can block the differences between different sub-class objects, write generic code, and make general programming to adapt to the changing needs.In general, it is the reuse of interfaces .So t

address of the virtual function of the called subclass cannot be given).Therefore, this function address is bound in the execution period (late bonding). The conclusion is that overloading is only a linguistic feature, independent of polymorphism, and irrelevant to object-oriented !about polymorphism " don't be foolish. Assuming it's not late binding, it's not polymorphic.”So what is the role of

new subclasses does not affect the polymorphism, inheritance, and the operation and manipulation of other attributes of existing classes. In fact, new subclasses are more likely to get polymorphic functions. For example, it is easy to add the polymorphism of sphere class on the basis of realizing the multi-state of cone, semi-cone and hemispherical body. 3.interface (interface-ability).

inheritance relationship, Java inheritance is a single inheritance, a class can have only one parent class, breaking the limitations of inheritance.2. External provision of rules (USB interface)3. Reduce the coupling of the program (can achieve modular development, define the rules, everyone to implement their own modules, improve the efficiency of development)1.7 The difference between an interface and an

properties and methods that are created by subclasses, and the OO development paradigm is roughly: dividing objects → abstract classes → organizing classes into hierarchical structures (inheritance and compositing) → Designing and implementing several stages with classes and instances.Polymorphicpolymorphism (polymorphism) is a technique that allows you to set a parent object to be equal to one or more of his child objects, after which the parent obj

JAVA object-oriented features polymorphism, java object-orientedPolymorphism refers to the multi-form inheritance of objects, which is the basis for the implementation of polymorphism. Do not forget that the child parent class must have an inheritance relationship. polymorphism