Access Modifiers

Access modifiers (Specifiers) in Java are keywords that control the visibility and accessibility of classes, methods, and variables. They ensure encapsulation, data hiding, and maintainability of code by regulating access to members.

Access Specifiers in Java

Public

Description

public access modifier allows unrestricted access to a class, method, or variable from any other class.

Example

public class PublicExample {
    public int publicVariable = 10;

    public void publicMethod() {
        System.out.println("This is a public method.");
    }
}

Private

Description

private access modifier restricts access to members within the same class. They are not accessible from outside the class.

Example

public class PrivateExample {
    private int privateVariable = 20;

    private void privateMethod() {
        System.out.println("This is a private method.");
    }
}

Protected

Description

protected access modifier allows access to members within the same package or subclasses, even if they are in different packages.

Example

public class ProtectedExample {
    protected int protectedVariable = 30;

    protected void protectedMethod() {
        System.out.println("This is a protected method.");
    }
}

Default (Package-private)

Description

Members with no access modifier (also known as package-private) are accessible only within the same package.

Example

class DefaultExample {
    int defaultVariable = 40;

    void defaultMethod() {
        System.out.println("This is a default method.");
    }
}

Brief Comparison Table

Access Modifier	Visibility	Accessible from Same Class	Accessible from Subclasses	Accessible from Same Package	Accessible from Different Package
public	Global	Yes	Yes	Yes	Yes
private	Local	Yes	No	No	No
protected	Package and Subclass	Yes	Yes	Yes	No
default	Package	Yes	No	Yes	No

Summary

• Public: Use when you want unrestricted access to members.

• Private: Use for encapsulation and to restrict access to members.

• Protected: Use when you want members accessible within subclasses or the same package.

• Default (Package-private): Use for package-level encapsulation and restricted access.

Choose the appropriate access modifier based on the desired level of encapsulation and access control required for your classes, methods, and variables.