What are the access modifiers in java

Access modifiers in Java control member visibility, there are four: public (all classes and packages), protected (same package and subclasses), default (same package) and private (only declared classes) .

Access modifiers in Java

In Java, access modifiers are used to control classes, methods, Visibility of fields and other members. There are four access modifiers, which are:

• public: Members are visible in all classes and packages.
• protected: Members are visible in the same package and in subclasses.
• default (or package access): Members are visible in the same package.
• private: Members are only visible within the class in which they are declared.

Usage

• public Modifiers are used on classes, methods and fields to make them visible in all classes and packages visible. This is the broadest visibility.
• protected Modifiers are typically used on methods and fields to allow subclasses to access them. This protects members from inappropriate access by other classes.
• default modifier is used implicitly when no other visibility modifier is explicitly specified. It restricts members to be visible to classes in the same package.
• private Modifiers are used on methods and fields that can only be accessed within the class in which they are declared. This visibility provides the strictest access control.

Example

// Public class
public class MyClass {

    // Protected method
    protected void myProtectedMethod() { }

    // Default field
    int myDefaultField;

    // Private constructor
    private MyClass() { }
}

In this example:

• MyClass is a public class that can Used in any class or package.
• myProtectedMethod is a protected method that can be used in MyClass itself as well as its subclasses.
• myDefaultField is a default field that can only be used in classes in the same package as MyClass. The constructor of
• MyClass is private and can only be used within MyClass itself.

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