private、protected
时间: 2023-09-21 11:05:11 浏览: 40
和public是C++中的三个访问控制关键字,用于控制类成员的访问权限。
private关键字用于指定只有在类内部才可以访问的成员变量和成员函数。这意味着在类的外部不能直接访问这些成员。只有通过类的公共接口(public成员函数)才能访问这些私有成员。
protected关键字用于指定只有在类内部和子类中才可以访问的成员变量和成员函数。这意味着在类的外部不能直接访问这些成员,但是在子类中可以通过继承来访问这些受保护的成员。
public关键字用于指定可以在类内部和类外部直接访问的成员变量和成员函数。这些成员可以通过类的对象和类的公共接口来访问。
相关问题
private protected public
private protected public是三种访问控制修饰符,用来控制类成员的访问权限。private表示只能在当前类内部访问,protected表示只能在当前类及其子类中访问,public表示可以被任何对象访问。在面向对象编程中,良好的封装和访问控制是保证代码质量和安全性的重要手段。
java private protected
Java has four access modifiers for classes, methods, and variables:
1. Public: The public access modifier means that the class, method, or variable can be accessed from anywhere in the program.
2. Private: The private access modifier means that the class, method, or variable can only be accessed within the same class.
3. Protected: The protected access modifier means that the class, method, or variable can only be accessed within the same class, or by a subclass in a different package.
4. Default: If no access modifier is specified, the class, method, or variable has default access, which means it can only be accessed within the same package.
Private members can only be accessed within the same class. This means that any other class cannot access the private member, even if it is in the same package.
Protected members can be accessed within the same class, as well as by a subclass in a different package. This means that any class that extends the class with the protected member can access it.
In general, it is best practice to use the most restrictive access modifier that still allows the necessary access to the member. This helps to ensure that the code is secure and maintainable.