java class inheritance

class object can use the method of the base class, but the method is not private (2) The base class pointer can point to a derived class object without converting the display type; the reference is also, the base class reference can reference the derived

--java Training, Android training, iOS training,. NET training look forward to sharing with you! ——Inheritance and Rewriting (extendsoverride) 1. Inheritance 1.1. The process of generalizationIn the previous case, the T class and J classes are defined, and through analysis, there are a lot of duplicate code in these tw

Read Catalogue First, the interfaceSecond, the internal class 　　multiple inheritance refers to the fact that a class can inherit behavior and characteristics from more than one parent class at the same time , but we know that Java only allows single

Inheritance of PHP classesThe inheritance of a PHP class refers to the creation of a new derived class that inherits data and methods from one or more previously defined classes, and can redefine or add new data and methods to establish the hierarchy or rank of the class.We call the existing

1. The inheritance of the class and the relationship between the father, son and grandson in life, Python, if Class A inherits Class B, then class A is called a subclass, and Class B is called a parent

() { }; function B (s1, S2) { } B.prototype = new A (); B.PROTOTYPE.B1 = function () { }; New B ("AB", "123"); As you can see, there is no way to upload S1 and S2 to a in this code, and there is an exception because there are no arguments for instantiating a as a prototype of B: Copy Code code as follows: S1 is undefined Solution The scope of S1 and S2 is only within B, and to pass them to a, you can only operate in B, using the application

that holds the name of the object/instance, called the object/instance propertyIn the Obj.name will first find the name in Obj's own namespace, can not find the class to find, the class can not find the parent class ... Throw an exception if you can't find it at the endSupplement to class attributesA: Where do the pro

same name, the subclass takes precedence over (overload), and therefore cannot overwrite: The Code is as follows: For (var m in A. prototype ){If (! B. prototype [m]) {// The parent class cannot overwrite the subclass method.B. prototype [m] = A. prototype [m];}} Postscript Considering that C #, Java and other advanced languages all discard multi-inheritance

same name, the subclass takes precedence over (overload), and therefore cannot overwrite: The code is as follows: For (var m in A. prototype ){If (! B. prototype [m]) {// the parent class cannot overwrite the subclass method.B. prototype [m] = A. prototype [m];}} Postscript Considering that C #, Java and other advanced languages all discard multi-inheritance

parentheses to call# He's the return value of the Get function2. Inheritance#目的是为了减少代码, reduce duplicate codeClass Ln: #父类 Money= ' 2000 ' def Make_money (self): Print (' Earn money ')Class Me (Ln): #子类PassPrint (Me.money) #继承父类 with a result of 2000Nhy=me ()Nhy.make_money ()If the method in the subclass is refactored, the refactoring method is theIf you modify the method of the parent

Fifth Chapter Succession1. Class Superclass sub-classInheritance: Extends (all inheritance sick a public inheritance, no private inheritance and protection inheritance)c+++: By:2. Using super (C # using base) to call the base class